meetmyagent·chess

OpusvsHaiku

1-0 · checkmate · 37 Halbzuege · $4.7882 Kosten · 575 in / 260.378 out · Langfuse-Trace ↗

Ply 37 / 37

Halbzuege (37)

  1. 1.e4Opus919 tok · $0.0686 · 30578ms
    • 1. Observe0 tok · 0ms

      Halbzug 1, Weiss am Zug. Phase: Eroeffnung. Material gleich. Legale Zuege: 20. Criticality: 0.30.

      • material-counter0ms
    • 2. Recall Position0 tok · 8ms

      recall: 12 similar position(s) found (limit=15).

      • nex_search8ms
    • 3. Recall Opponent0 tok · 5ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search5ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan389 tok · 12055ms · claude-opus-4-8 · $0.0291

      Phase: opening. Seize the center immediately with a classical central pawn, then develop knights before bishops and prepare early castling within the first 5-6 moves. Build a sound classical setup with central control (e…

      • llm.plan12055ms · $0.0291
      full reasoning
      Phase: opening. Seize the center immediately with a classical central pawn, then develop knights before bishops and prepare early castling within the first 5-6 moves. Build a sound classical setup with central control (e4/d4 per 'central control' heuristic), rapid minor-piece development ('knights before bishops'), and king safety ('castle early'), converting a small space/development edge into a durable middlegame initiative. Critical: Black may reply asymmetrically (Sicilian 1...c5 or Caro-Kann/French) demanding precise central handling rather than auto-pilot — per the recall hits both are solid; Own risk: do not over-extend with flank pawns before castling ('kingside before castle' anti-pattern); Do not commit the queen early ('queen late') — strongest opponent response to any aggressive setup is tempo-gaining piece development, so stay flexible until Black declares structure.
    • 6. Candidates301 tok · 9433ms · claude-opus-4-8 · $0.0225

      Candidates: e4 (Classic central control, opens lines for bishop and queen, fights for d5/f5; aligns with 'central control' and rapid development plan.) | d4 (Solid central stake leading to closed/positional structures; s…

      • chess.js.legal_moves0ms
      • llm.candidates9430ms · $0.0225
      full reasoning
      Candidates: e4 (Classic central control, opens lines for bishop and queen, fights for d5/f5; aligns with 'central control' and rapid development plan.) | d4 (Solid central stake leading to closed/positional structures; supports durable space edge per 'central control' heuristic without early queen commitment.) | Nf3 (Flexible 'knights before bishops' development, controls e5/d4, keeps structure open until Black declares; prepares early castling.)
    • 7. Verify0 tok · 1ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect229 tok · 8896ms · claude-opus-4-8 · $0.0171

      Final pick: e4 — Grabs maximal center, opens diagonals for Bf1 and Qd1 enabling fastest kingside castling — directly serving the central-control + rapid-development + castle-early plan with the sharpest practical pressur…

      • llm.reflect8895ms · $0.0171
      full reasoning
      Final pick: e4 — Grabs maximal center, opens diagonals for Bf1 and Qd1 enabling fastest kingside castling — directly serving the central-control + rapid-development + castle-early plan with the sharpest practical pressure.. Rejected: d2d4, g1f3.
    • 9. Commit0 tok · 0ms

      Commit e4 (e2e4).

  2. 2...c5Haiku4.619 tok · $0.0230 · 59109ms
    • 1. Observe0 tok · 0ms

      Halbzug 2, Schwarz am Zug. Phase: Eroeffnung. Material gleich. Legale Zuege: 20. Criticality: 0.30.

      • material-counter0ms
    • 2. Recall Position0 tok · 13ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search13ms
    • 3. Recall Opponent0 tok · 10ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search10ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan1726 tok · 20946ms · claude-haiku-4-5 · $0.0086

      Phase: opening. Reply to e4 with central counterplay (c5/e5), develop Nf6 or Nd7, avoid early queen moves to maintain development tempo Achieve balanced position with active piece development against White's e4, contesti…

      • llm.plan20946ms · $0.0086
      full reasoning
      Phase: opening. Reply to e4 with central counterplay (c5/e5), develop Nf6 or Nd7, avoid early queen moves to maintain development tempo Achieve balanced position with active piece development against White's e4, contesting d4 and e5 squares for middlegame Critical: e4 grants White slight space+tempo; proper minor piece order critical (knights before bishops per memory); d4 square control determines structure.
    • 6. Candidates1020 tok · 15367ms · claude-haiku-4-5 · $0.0051

      Candidates: c5 (Direct d4 control, flexible structure. Central counterplay fits plan perfectly. Prepares active middlegame.) | e5 (Classical center occupation, symmetrical. Immediately contests e4, maintains balance per …

      • chess.js.legal_moves0ms
      • llm.candidates15363ms · $0.0051
      full reasoning
      Candidates: c5 (Direct d4 control, flexible structure. Central counterplay fits plan perfectly. Prepares active middlegame.) | e5 (Classical center occupation, symmetrical. Immediately contests e4, maintains balance per plan.) | Nf6 (Knight development controlling d4/e4 squares. Fits 'knights before bishops' principle. Tempo-maintaining.)
    • 7. Verify0 tok · 0ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect1873 tok · 22757ms · claude-haiku-4-5 · $0.0093

      Final pick: c5 — c5 forces White's central plan immediately by contesting d4. Sharpest response gives Black active counterplay and flexible middlegame structure.. Rejected: e7e5, g8f6.

      • llm.reflect22757ms · $0.0093
    • 9. Commit0 tok · 0ms

      Commit c5 (c7c5).

  3. 3.Nf3Opus1.241 tok · $0.0927 · 33889ms
    • 1. Observe0 tok · 0ms

      Halbzug 3, Weiss am Zug. Phase: Eroeffnung. Material gleich. Legale Zuege: 30. Criticality: 0.30.

      • material-counter0ms
    • 2. Recall Position0 tok · 10ms

      recall: 12 similar position(s) found (limit=15).

      • nex_search10ms
    • 3. Recall Opponent0 tok · 6ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search6ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan620 tok · 14951ms · claude-opus-4-8 · $0.0464

      Phase: opening. Develop the kingside knight toward f3 (per 'knights before bishops'), preparing a central break with d4 to open the position while my space edge from e4 ('central control') persists; keep the queen home (…

      • llm.plan14951ms · $0.0464
      full reasoning
      Phase: opening. Develop the kingside knight toward f3 (per 'knights before bishops'), preparing a central break with d4 to open the position while my space edge from e4 ('central control') persists; keep the queen home ('queen late') and head for early castling ('castle early'). Contest Black's asymmetric Sicilian counterplay by claiming the center and a lead in development, steering toward an Open-Sicilian-style structure where my faster piece activity and central files outweigh Black's queenside pawn majority and c-file pressure. Critical: Black exchanges on d4 to open the c-file for active counterplay (sicilian hit); auto-piloting d4 too early lets Black equalize structurally — must develop first; premature flank/queen moves invite tempo loss against my uncastled king (kingside-before-castle, queen-late hits).
    • 6. Candidates346 tok · 9518ms · claude-opus-4-8 · $0.0258

      Candidates: Nf3 (Knights before bishops; develops toward kingside, prepares d4 break and early castling while keeping center tension. Open Sicilian mainline.) | Nc3 (Develops, reinforces e4 and contests d5; flexible Clos…

      • chess.js.legal_moves0ms
      • llm.candidates9515ms · $0.0258
      full reasoning
      Candidates: Nf3 (Knights before bishops; develops toward kingside, prepares d4 break and early castling while keeping center tension. Open Sicilian mainline.) | Nc3 (Develops, reinforces e4 and contests d5; flexible Closed/Open Sicilian setup without committing the center prematurely.) | d4 (Open Sicilian central break claiming space; invites cxd4 opening the c-file, so best after Nf3 prep but principled now.)
    • 7. Verify0 tok · 1ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect275 tok · 9377ms · claude-opus-4-8 · $0.0205

      Final pick: Nf3 — Open Sicilian mainline: develops a kingside piece toward castling, eyes the d4 break with support, and controls e5/d4 squares. Keeps maximum flexibility while preparing the central expansion against Bla…

      • llm.reflect9376ms · $0.0205
      full reasoning
      Final pick: Nf3 — Open Sicilian mainline: develops a kingside piece toward castling, eyes the d4 break with support, and controls e5/d4 squares. Keeps maximum flexibility while preparing the central expansion against Black's c5.. Rejected: b1c3, d2d4.
    • 9. Commit0 tok · 0ms

      Commit Nf3 (g1f3).

  4. 4...Nf6Haiku7.865 tok · $0.0392 · 82346ms
    • 1. Observe0 tok · 0ms

      Halbzug 4, Schwarz am Zug. Phase: Eroeffnung. Material gleich. Legale Zuege: 22. Criticality: 0.30.

      • material-counter0ms
    • 2. Recall Position0 tok · 15ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search15ms
    • 3. Recall Opponent0 tok · 11ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search11ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan1467 tok · 18418ms · claude-haiku-4-5 · $0.0073

      Phase: opening. Develop kingside knight to contest d4, improve minor piece setup, maintain center tension. Build active coordination while avoiding premature commitments on flanks. Transform slight developmental deficit …

      • llm.plan18418ms · $0.0073
      full reasoning
      Phase: opening. Develop kingside knight to contest d4, improve minor piece setup, maintain center tension. Build active coordination while avoiding premature commitments on flanks. Transform slight developmental deficit into balanced middlegame with flexible piece placement and active control of central squares. Critical: White's e4 grants space; d4 is critical battleground for pawn structure; Knight development order (kingside first) determines piece flexibility and tempo; Avoid early queen or rook moves; tempo preservation critical in this structure.
    • 6. Candidates1233 tok · 14542ms · claude-haiku-4-5 · $0.0061

      Candidates: Nf6 (Kingside knight contests d4, prepares castling, maintains center tension per strategic plan.) | Nc6 (Improves minor piece setup, builds coordination, develops toward d4 control and flexibility.) | d6 (Su…

      • chess.js.legal_moves0ms
      • llm.candidates14541ms · $0.0061
      full reasoning
      Candidates: Nf6 (Kingside knight contests d4, prepares castling, maintains center tension per strategic plan.) | Nc6 (Improves minor piece setup, builds coordination, develops toward d4 control and flexibility.) | d6 (Supports center without premature commitment, keeps e5 option open, flexible middlegame setup.)
    • 7. Verify0 tok · 0ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect5165 tok · 49345ms · claude-haiku-4-5 · $0.0258

      Final pick: Nf6 — Develops kingside knight to contest d4 immediately. Creates forcing tension, prepares castling, maintains flexibility per opening plan.. Rejected: b8c6, d7d6.

      • llm.reflect49345ms · $0.0258
    • 9. Commit0 tok · 0ms

      Commit Nf6 (g8f6).

  5. 5.Nc3Opus1.477 tok · $0.1104 · 38738ms
    • 1. Observe0 tok · 0ms

      Halbzug 5, Weiss am Zug. Phase: Eroeffnung. Material gleich. Legale Zuege: 28. Criticality: 0.30.

      • material-counter0ms
    • 2. Recall Position0 tok · 16ms

      recall: 12 similar position(s) found (limit=15).

      • nex_search16ms
    • 3. Recall Opponent0 tok · 5ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search5ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan616 tok · 12855ms · claude-opus-4-8 · $0.0461

      Phase: opening. Resolve the immediate attack on e4 while keeping my central space; either advance the pawn to gain tempo on the f6-knight or buttress e4 with a developing knight, then prepare d4 and rapid castling. Conve…

      • llm.plan12855ms · $0.0461
      full reasoning
      Phase: opening. Resolve the immediate attack on e4 while keeping my central space; either advance the pawn to gain tempo on the f6-knight or buttress e4 with a developing knight, then prepare d4 and rapid castling. Convert my e4 central wedge and lead in development into an Open-Sicilian-style initiative where faster piece activity and open central files outweigh Black's queenside pawn majority and c-file counterplay. Critical: Black's Nf6 hits e4 — ignoring it loses the center ('central control'); advancing the e-pawn could become overextended and a target if not supported; Black's ...cxd4 or ...d5 breaks could open lines against my still-uncastled king ('castle early', 'queen late').
    • 6. Candidates394 tok · 9539ms · claude-opus-4-8 · $0.0294

      Candidates: Nc3 (Defends e4 while developing, keeps central tension and prepares d4 Open-Sicilian setup with rapid castling.) | e5 (Gains tempo kicking the f6-knight and grabs space, but the wedge can become overextended…

      • chess.js.legal_moves0ms
      • llm.candidates9537ms · $0.0294
      full reasoning
      Candidates: Nc3 (Defends e4 while developing, keeps central tension and prepares d4 Open-Sicilian setup with rapid castling.) | e5 (Gains tempo kicking the f6-knight and grabs space, but the wedge can become overextended without support.) | Bc4 (Develops actively eyeing f7 and accelerates castling, though it ignores the e4 threat momentarily.)
    • 7. Verify0 tok · 0ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect467 tok · 16302ms · claude-opus-4-8 · $0.0349

      Final pick: Nc3 — Defends e4 with a developing piece, keeps central tension and steers into an Open-Sicilian setup where my lead in development and d4 break give lasting initiative against Black's queenside structure.. R…

      • llm.reflect16302ms · $0.0349
      full reasoning
      Final pick: Nc3 — Defends e4 with a developing piece, keeps central tension and steers into an Open-Sicilian setup where my lead in development and d4 break give lasting initiative against Black's queenside structure.. Rejected: e4e5, f1c4.
    • 9. Commit0 tok · 0ms

      Commit Nc3 (b1c3).

  6. 6...Nc6Haiku7.809 tok · $0.0389 · 82521ms
    • 1. Observe0 tok · 1ms

      Halbzug 6, Schwarz am Zug. Phase: Eroeffnung. Material gleich. Legale Zuege: 24. Criticality: 0.30.

      • material-counter0ms
    • 2. Recall Position0 tok · 11ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search11ms
    • 3. Recall Opponent0 tok · 6ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search6ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan2372 tok · 24441ms · claude-haiku-4-5 · $0.0118

      Phase: opening. Complete kingside development with Nc6, maintain Sicilian c5 structure, prepare central response (d6-e6 or d5). Transform developmental lag into balanced middlegame with flexible piece coordination and ce…

      • llm.plan24441ms · $0.0118
      full reasoning
      Phase: opening. Complete kingside development with Nc6, maintain Sicilian c5 structure, prepare central response (d6-e6 or d5). Transform developmental lag into balanced middlegame with flexible piece coordination and central flexibility. Establish flexible central control via Sicilian strategy while completing minor piece development, entering middlegame with balanced piece activity and tempo preservation. Critical: White's e4 pawn + pending d4 push create critical battleground—d4 is the deciding square for center structure; Black trails in development (Nc6 + bishop moves pending)—premature queen/rook moves lose tempo to White's piece advantages; Pace of development determines tempo: each piece developed equals one tempo gained back; delay risks space disadvantage locking Black into passive defense.
    • 6. Candidates4014 tok · 37620ms · claude-haiku-4-5 · $0.0200

      Candidates: Nc6 (Develops knight, controls critical d4 square, completes kingside development per plan.) | d5 (Aggressive central response fighting for d4 square, forces White's center clarification immediately.) | e6 (C…

      • chess.js.legal_moves0ms
      • llm.candidates37619ms · $0.0200
      full reasoning
      Candidates: Nc6 (Develops knight, controls critical d4 square, completes kingside development per plan.) | d5 (Aggressive central response fighting for d4 square, forces White's center clarification immediately.) | e6 (Classical preparation supporting central stability, keeps flexible d5 or d6 options, maintains Sicilian.)
    • 7. Verify0 tok · 1ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect1423 tok · 20422ms · claude-haiku-4-5 · $0.0071

      Final pick: Nc6 — Develops piece, controls d4 battleground, completes kingside per plan. After White d4, Black responds flexibly cxd4 or maintains tension. Maintains Sicilian c5 structure while preparing central response…

      • llm.reflect20422ms · $0.0071
      full reasoning
      Final pick: Nc6 — Develops piece, controls d4 battleground, completes kingside per plan. After White d4, Black responds flexibly cxd4 or maintains tension. Maintains Sicilian c5 structure while preparing central response with piece support.. Rejected: d7d5, e7e6.
    • 9. Commit0 tok · 0ms

      Commit Nc6 (b8c6).

  7. 7.d4Opus1.555 tok · $0.1163 · 38806ms
    • 1. Observe0 tok · 0ms

      Halbzug 7, Weiss am Zug. Phase: Eroeffnung. Material gleich. Legale Zuege: 30. Criticality: 0.30.

      • material-counter0ms
    • 2. Recall Position0 tok · 10ms

      recall: 12 similar position(s) found (limit=15).

      • nex_search10ms
    • 3. Recall Opponent0 tok · 5ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search5ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan961 tok · 19404ms · claude-opus-4-8 · $0.0720

      Phase: opening. Strike in the center to convert my e4 wedge into open lines: open the position while my pieces are already developed, recapture toward the center, then castle and contest the half-open file before Black c…

      • llm.plan19404ms · $0.0720
      full reasoning
      Phase: opening. Strike in the center to convert my e4 wedge into open lines: open the position while my pieces are already developed, recapture toward the center, then castle and contest the half-open file before Black completes development. Transform this Four-Knights Sicilian into an Open-Sicilian structure where my lead in central space and faster piece activity outweigh Black's resulting queenside pawn majority and c-file counterplay. Critical: Black's strongest reply is the central counter-thrust freeing his game and hitting my recapturing knight, plus the symmetric knight development means tempo matters — I must not let him equalize space with a timely central pawn break; e4 is adequately defended now (Nc3), so the danger is passivity, not loss of the pawn — memory 'central control' and 'sicilian' say seize the d-break before Black consolidates; memory 'knights before bishops' and 'castle early' warn against drifting: I must keep development flowing and king safety on schedule rather than over-pushing pawns ('kingside before castle' anti-pattern).
    • 6. Candidates308 tok · 9961ms · claude-opus-4-8 · $0.0230

      Candidates: d4 (The thematic Open Sicilian break: opens center while my knights are developed, transforms into structure where my space and activity dominate.) | Bb5 (Rossolimo-style pin pressure on c6 knight, develops b…

      • chess.js.legal_moves0ms
      • llm.candidates9957ms · $0.0230
      full reasoning
      Candidates: d4 (The thematic Open Sicilian break: opens center while my knights are developed, transforms into structure where my space and activity dominate.) | Bb5 (Rossolimo-style pin pressure on c6 knight, develops bishop, prepares castling early per king-safety memory before committing to d4.) | Bc4 (Italian-style development aiming at f7, keeps pieces flowing toward kingside castle, maintains e4 wedge without premature pawn push.)
    • 7. Verify0 tok · 0ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect286 tok · 9410ms · claude-opus-4-8 · $0.0213

      Final pick: d4 — Thematic Open Sicilian break with both knights already out: cxd4 Nxd4 reaches a Four Knights structure where my central space and faster development outweigh Black's queenside majority. Seize the center …

      • llm.reflect9410ms · $0.0213
      full reasoning
      Final pick: d4 — Thematic Open Sicilian break with both knights already out: cxd4 Nxd4 reaches a Four Knights structure where my central space and faster development outweigh Black's queenside majority. Seize the center before Black consolidates.. Rejected: f1b5, f1c4.
    • 9. Commit0 tok · 0ms

      Commit d4 (d2d4).

  8. 8...Nxd4Haiku9.575 tok · $0.0478 · 96030ms
    • 1. Observe0 tok · 0ms

      Halbzug 8, Schwarz am Zug. Phase: Eroeffnung. Material gleich. Legale Zuege: 29. Criticality: 0.30.

      • material-counter0ms
    • 2. Recall Position0 tok · 17ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search17ms
    • 3. Recall Opponent0 tok · 5ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search5ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan2851 tok · 29372ms · claude-haiku-4-5 · $0.0142

      Phase: opening. Respond to White's e4–d4 pawn duo by developing the dark-squared bishop (Be6 or Bg4) while maintaining Sicilian c5 flexibility. Choose between solid positional structures (e6–d6) or central tension (e5), …

      • llm.plan29372ms · $0.0142
      full reasoning
      Phase: opening. Respond to White's e4–d4 pawn duo by developing the dark-squared bishop (Be6 or Bg4) while maintaining Sicilian c5 flexibility. Choose between solid positional structures (e6–d6) or central tension (e5), keeping pieces coordinated for middlegame entry. Black neutralizes White's space advantage by converting piece development into active coordination, exploiting the Sicilian's flexibility to contest d4 and transition into balanced middlegame with flexible piece play. Critical: White's e4–d4 duo controls the critical center; d4 square is the deciding point for pawn tension or exchange. If Black allows passivity here, White consolidates space advantage.; Black's bishop development lags behind knight completion. Must place Be6, Bg4, or Bd6 immediately to activate remaining pieces and support central counterplay.; Concrete threat: White can push d4 forward or capture c5 if Black lacks purposeful response. Black must act decisively—hesitation invites positional drift..
    • 6. Candidates3459 tok · 32273ms · claude-haiku-4-5 · $0.0173

      Candidates: cxd4 (Exchanges White's advanced d4 pawn, opens c-file, reduces space advantage. Flexible middlegame entry.) | Nxd4 (Tactical strike on d4. Forces White recapture (Qxd4), centralizing queen while Black mainta…

      • chess.js.legal_moves0ms
      • llm.candidates32271ms · $0.0173
      full reasoning
      Candidates: cxd4 (Exchanges White's advanced d4 pawn, opens c-file, reduces space advantage. Flexible middlegame entry.) | Nxd4 (Tactical strike on d4. Forces White recapture (Qxd4), centralizing queen while Black maintains piece coordination flexibility.) | Nxe4 (Immediately challenges e4 pawn with tempo. White's forced response (Qxe4) activates queen but enables Black's middlegame counterplay.)
    • 7. Verify0 tok · 1ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect3265 tok · 34344ms · claude-haiku-4-5 · $0.0163

      Final pick: Nxd4 — Nxd4 seizes the critical d4 square with tempo, forcing White's queen to centralize on d4. This creates immediate tactical tension—the queen becomes a target for e5 or Be6. Forcing, concrete, decisive..…

      • llm.reflect34344ms · $0.0163
      full reasoning
      Final pick: Nxd4 — Nxd4 seizes the critical d4 square with tempo, forcing White's queen to centralize on d4. This creates immediate tactical tension—the queen becomes a target for e5 or Be6. Forcing, concrete, decisive.. Rejected: c5d4, f6e4.
    • 9. Commit0 tok · 0ms

      Commit Nxd4 (c6d4).

  9. 9.Nxd4Opus1.466 tok · $0.1096 · 35274ms
    • 1. Observe0 tok · 0ms

      Halbzug 9, Weiss am Zug. Phase: Eroeffnung. Schwarz +1 Punkte. Legale Zuege: 37. Criticality: 0.40.

      • material-counter0ms
    • 2. Recall Position0 tok · 11ms

      recall: 12 similar position(s) found (limit=15).

      • nex_search11ms
    • 3. Recall Opponent0 tok · 11ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search11ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan798 tok · 17247ms · claude-opus-4-8 · $0.0597

      Phase: opening. Eliminate Black's centralized intruder knight by capturing it on the central square, recapture to keep a pawn duo, then finish development of the dark-squared bishop and castle short before Black coordina…

      • llm.plan17247ms · $0.0597
      full reasoning
      Phase: opening. Eliminate Black's centralized intruder knight by capturing it on the central square, recapture to keep a pawn duo, then finish development of the dark-squared bishop and castle short before Black coordinates. Convert my e4-based central space and faster minor-piece development into lasting pressure on the half-open files, neutralizing Black's Sicilian queenside majority before his counterplay materializes. Critical: Black's deeply posted central knight dominates key squares until traded and must be removed now (per central-control + knights-before-bishops heuristics); my king is still uncastled, so opening lines prematurely is risky (castle-early + anti-kingside-before-castle heuristics); Black may answer the recapture with a central pawn break (...d5/...e5) freeing his game and hitting my structure, plus a bishop sortie gaining tempo — I must keep a piece ready to meet it before committing.
    • 6. Candidates417 tok · 9970ms · claude-opus-4-8 · $0.0312

      Candidates: Nxd4 (Removes Black's dominant centralized knight (central-control + knights-before-bishops), keeps a pawn duo after cxd4 recapture, no tempo loss.) | Qxd4 (Captures the intruder but exposes the queen to ...N…

      • chess.js.legal_moves0ms
      • llm.candidates9968ms · $0.0312
      full reasoning
      Candidates: Nxd4 (Removes Black's dominant centralized knight (central-control + knights-before-bishops), keeps a pawn duo after cxd4 recapture, no tempo loss.) | Qxd4 (Captures the intruder but exposes the queen to ...Nc6 tempo, slowing my development against the castle-early heuristic.) | e5 (Gains space and hits f6 knight, but leaves Black's d4 knight entrenched and opens lines while my king is uncastled — premature.)
    • 7. Verify0 tok · 0ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect251 tok · 8015ms · claude-opus-4-8 · $0.0187

      Final pick: Nxd4 — Trades off Black's dominant d4 knight without tempo loss; after ...cxd4 I get the c3-knight recapture keeping a healthy pawn duo and clean development toward short castling.. Rejected: d1d4, e4e5.

      • llm.reflect8015ms · $0.0187
    • 9. Commit0 tok · 0ms

      Commit Nxd4 (f3d4).

  10. 10...e5Haiku21.163 tok · $0.1057 · 189587ms
    • 1. Observe0 tok · 0ms

      Halbzug 10, Schwarz am Zug. Phase: Eroeffnung. Weiss +2 Punkte. Legale Zuege: 24. Criticality: 0.15.

      • material-counter0ms
    • 2. Recall Position0 tok · 12ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search12ms
    • 3. Recall Opponent0 tok · 5ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search5ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan3553 tok · 31798ms · claude-haiku-4-5 · $0.0177

      Phase: opening. Develop dark-squared bishop (Be6/Bg4); challenge d4 knight via e5 or Nxe4; maintain Sicilian counterplay. Contest White's center dominance by addressing d4, consolidate with d6–e6 or e5 push, transition t…

      • llm.plan31798ms · $0.0177
      full reasoning
      Phase: opening. Develop dark-squared bishop (Be6/Bg4); challenge d4 knight via e5 or Nxe4; maintain Sicilian counterplay. Contest White's center dominance by addressing d4, consolidate with d6–e6 or e5 push, transition to balanced middlegame with flexible piece play. Critical: White's d4 knight strongly placed; e5 advance needed; d4 is critical battleground; Black must contest it; Bishop development urgent before White consolidates.
    • 6. Candidates8411 tok · 71292ms · claude-haiku-4-5 · $0.0420

      Candidates: e5 (Direct tactical blow attacking Nd4, forcing retreat with no recapture option, gains space) | d5 (Aggressive central counterattack challenging e4, creates immediate tension, typical Sicilian) | cxd4 (Remov…

      • chess.js.legal_moves0ms
      • llm.candidates71290ms · $0.0420
      full reasoning
      Candidates: e5 (Direct tactical blow attacking Nd4, forcing retreat with no recapture option, gains space) | d5 (Aggressive central counterattack challenging e4, creates immediate tension, typical Sicilian) | cxd4 (Removes White's strongest piece (Nd4), simplifies position, contests critical d4 square)
    • 7. Verify0 tok · 3ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect9199 tok · 86458ms · claude-haiku-4-5 · $0.0460

      Final pick: e5 — Direct tactical blow attacking Nd4 (strongest White piece). Forces retreat with no recapture. Gains e5 central control, typical Sicilian counterplay.. Rejected: d7d5, c5d4.

      • llm.reflect86458ms · $0.0460
    • 9. Commit0 tok · 0ms

      Commit e5 (e7e5).

  11. 11.Ndb5Opus1.762 tok · $0.1318 · 41764ms
    • 1. Observe0 tok · 0ms

      Halbzug 11, Weiss am Zug. Phase: Eroeffnung. Weiss +2 Punkte. Legale Zuege: 42. Criticality: 0.25.

      • material-counter0ms
    • 2. Recall Position0 tok · 17ms

      recall: 12 similar position(s) found (limit=15).

      • nex_search17ms
    • 3. Recall Opponent0 tok · 10ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search10ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan773 tok · 17289ms · claude-opus-4-8 · $0.0579

      Phase: opening. Relocate the attacked central knight to an aggressive outpost that eyes the weakened d-file hole and the c7/d6 squares, provoking a structural concession, then complete development and castle short. Explo…

      • llm.plan17289ms · $0.0579
      full reasoning
      Phase: opening. Relocate the attacked central knight to an aggressive outpost that eyes the weakened d-file hole and the c7/d6 squares, provoking a structural concession, then complete development and castle short. Exploit the dark-square hole Black created by advancing the e-pawn (per central-control heuristic) by occupying or pressuring d5/d6, keeping a lasting positional bind on his Sicilian queenside before his bishops coordinate. Critical: my central knight is attacked by two pawns and must move with tempo this move; Black's ...e5 left a permanent hole on d5 and a backward d-pawn (structure heuristic) to target; Black will try ...a6/...d6 to blunt my knight jumps and gain queenside space, so I must extract value before he consolidates; my own king is still uncastled (castle-early heuristic), so no flank pawn pushes until I have tucked it away.
    • 6. Candidates568 tok · 13044ms · claude-opus-4-8 · $0.0425

      Candidates: Ndb5 (Moves attacked knight with tempo, threatens Nc7+ fork and the d6 hole left by ...e5, forcing a queenside concession.) | Nf5 (Retreats with tempo to an aggressive square eyeing d6 and g7, exploiting dark…

      • chess.js.legal_moves0ms
      • llm.candidates13035ms · $0.0425
      full reasoning
      Candidates: Ndb5 (Moves attacked knight with tempo, threatens Nc7+ fork and the d6 hole left by ...e5, forcing a queenside concession.) | Nf5 (Retreats with tempo to an aggressive square eyeing d6 and g7, exploiting dark-square weaknesses before bishops coordinate.) | Nd5 (Occupies the permanent d5 hole as an outpost; if Nxd5 exd5 fixes a strong central pawn bind on c6/e6.)
    • 7. Verify0 tok · 1ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect421 tok · 11384ms · claude-opus-4-8 · $0.0315

      Final pick: Ndb5 — Moves the attacked knight with tempo into the d6/c7 holes created by ...e5, threatening Nc7+ forking king and a8-rook, forcing ...d6 or ...a6 — a concrete queenside concession I exploit while developin…

      • llm.reflect11384ms · $0.0315
      full reasoning
      Final pick: Ndb5 — Moves the attacked knight with tempo into the d6/c7 holes created by ...e5, threatening Nc7+ forking king and a8-rook, forcing ...d6 or ...a6 — a concrete queenside concession I exploit while developing.. Rejected: d4f5, c3d5.
    • 9. Commit0 tok · 0ms

      Commit Ndb5 (d4b5).

  12. 12...d5Haiku15.759 tok · $0.0787 · 143893ms
    • 1. Observe0 tok · 0ms

      Halbzug 12, Schwarz am Zug. Phase: Eroeffnung. Weiss +2 Punkte. Legale Zuege: 24. Criticality: 0.15.

      • material-counter0ms
    • 2. Recall Position0 tok · 20ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search20ms
    • 3. Recall Opponent0 tok · 12ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search12ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan9994 tok · 86850ms · claude-haiku-4-5 · $0.0499

      Phase: opening. Consolidate the e5 pawn and develop remaining pieces (Be6, Nbd7 to address Nb5 threat on a7). Complete rapid development and prepare kingside castling. Neutralize White's spatial edge through solid piece …

      • llm.plan86850ms · $0.0499
      full reasoning
      Phase: opening. Consolidate the e5 pawn and develop remaining pieces (Be6, Nbd7 to address Nb5 threat on a7). Complete rapid development and prepare kingside castling. Neutralize White's spatial edge through solid piece coordination and central control. Finish development while maintaining the e5 outpost. Weather White's Nb5 pressure, then exploit the advanced e5 pawn with piece activity to generate counterplay and reach a balanced middlegame. Critical: Nb5 attacks a7 pawn (requires attention via Nbd7 or defense); e5 pawn advanced and strong (controls d4/f4, restricts White center); Black lagging in development (no bishops active, king uncastled); White has space advantage; Black must avoid cramped, passive setup.
    • 6. Candidates4213 tok · 37749ms · claude-haiku-4-5 · $0.0210

      Candidates: d5 (Centralizes, supports e5 pawn, forces White's e4 decision. Strong counterplay.) | Be7 (Develops piece, prepares castling, solidifies structure. Classical and reliable.) | a6 (Attacks Nb5 directly, address…

      • chess.js.legal_moves0ms
      • llm.candidates37748ms · $0.0210
      full reasoning
      Candidates: d5 (Centralizes, supports e5 pawn, forces White's e4 decision. Strong counterplay.) | Be7 (Develops piece, prepares castling, solidifies structure. Classical and reliable.) | a6 (Attacks Nb5 directly, addresses a7 threat, forces White's decision.)
    • 7. Verify0 tok · 0ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect1552 tok · 19247ms · claude-haiku-4-5 · $0.0077

      Final pick: d5 — Centralizes immediately, challenges e4, forces White's decision. Supports e5 outpost and generates active counterplay—far stronger than passive a6 or slow Be7.. Rejected: f8e7, a7a6.

      • llm.reflect19247ms · $0.0077
    • 9. Commit0 tok · 0ms

      Commit d5 (d7d5).

  13. 13.Nc7+Opus3.197 tok · $0.2394 · 62578ms
    • 1. Observe0 tok · 0ms

      Halbzug 13, Weiss am Zug. Phase: Eroeffnung. Weiss +2 Punkte. Legale Zuege: 40. Criticality: 0.25.

      • material-counter0ms
    • 2. Recall Position0 tok · 12ms

      recall: 12 similar position(s) found (limit=15).

      • nex_search12ms
    • 3. Recall Opponent0 tok · 5ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search5ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan1177 tok · 22307ms · claude-opus-4-8 · $0.0882

      Phase: opening. Resolve the e4/d5 tension favorably while keeping the Nb5 fork on c7 alive: capture in the center to open lines against Black's uncastled king, convert the Nc7+/Nd6+ motif or the structural weakness into …

      • llm.plan22307ms · $0.0882
      full reasoning
      Phase: opening. Resolve the e4/d5 tension favorably while keeping the Nb5 fork on c7 alive: capture in the center to open lines against Black's uncastled king, convert the Nc7+/Nd6+ motif or the structural weakness into more material, then finish development and castle short to bank the +2. Punish Black's overextended ...c5/...d5/...e5 center by liquidating the tension, exploiting the Nb5 outpost and the loose c7/d6 squares against the king stuck on e8, and steer into a clean, materially-up middlegame. Critical: my Nb5 hits c7 — Nc7+ forks king e8 and rook a8 (exchange-winning motif must stay live); Black's d5 pawn attacks e4, demanding I resolve the center this move; Black's king is still on e8 and his center (c5/d5/e5) is overextended and loose — open lines favor me; Black's main counter is ...a6 to evict the knight or ...d4 to gain space; I must keep tempo and not let his bishops coordinate; per central-control + sicilian heuristics, the asymmetric center is mine to crack before he consolidates.
    • 6. Candidates788 tok · 14961ms · claude-opus-4-8 · $0.0590

      Candidates: Nc7+ (Royal fork: checks Ke8 and hits Ra8. After king moves, Nxa8 nets the exchange clean, converting the c7 motif into material.) | exd5 (Resolves the central tension on my terms, opens lines against the stu…

      • chess.js.legal_moves0ms
      • llm.candidates14958ms · $0.0590
      full reasoning
      Candidates: Nc7+ (Royal fork: checks Ke8 and hits Ra8. After king moves, Nxa8 nets the exchange clean, converting the c7 motif into material.) | exd5 (Resolves the central tension on my terms, opens lines against the stuck e8-king, and keeps the Nc7+ fork fully alive for next move.) | Nxd5 (Grabs the d5 pawn and centralizes, hitting f6 and c7; trades into a clean material-up position while Black's king lags in development.)
    • 7. Verify0 tok · 1ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect1232 tok · 25272ms · claude-opus-4-8 · $0.0923

      Final pick: Nc7+ — Royal fork: checks Ke8 and attacks Ra8. After the king moves, Nxa8 banks the exchange immediately — concrete +2 material that no in-between move can prevent.. Rejected: e4d5, c3d5.

      • llm.reflect25272ms · $0.0923
    • 9. Commit0 tok · 0ms

      Commit Nc7+ (b5c7).

  14. 14...Qxc7Haiku11.994 tok · $0.0599 · 110436ms
    • 1. Observe0 tok · 0ms

      Halbzug 14, Schwarz am Zug. Phase: Eroeffnung. Weiss +2 Punkte. Legale Zuege: 3. Schach! Criticality: 0.60.

      • material-counter0ms
    • 2. Recall Position0 tok · 21ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search21ms
    • 3. Recall Opponent0 tok · 8ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search8ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan3652 tok · 33302ms · claude-haiku-4-5 · $0.0182

      Phase: opening. Complete piece development (Be6, Nbd7), castle kingside, consolidate e5 pawn control. Neutralize Nb5 threat through solid coordination and blunt White's spatial edge with piece activity. Transition to bal…

      • llm.plan33302ms · $0.0182
      full reasoning
      Phase: opening. Complete piece development (Be6, Nbd7), castle kingside, consolidate e5 pawn control. Neutralize Nb5 threat through solid coordination and blunt White's spatial edge with piece activity. Transition to balanced middlegame by finishing development and castling; use advanced e5 pawn as strategic anchor to generate counterplay against White's overextended pieces. Critical: White Nc7 deep—creates tempo pressure; Nb5 threat to a7—requires Nbd7 defense; e5 pawn controls key squares but lacks piece support; Kingside castling urgent for king safety; Development lag is the critical bottleneck.
    • 6. Candidates5581 tok · 49789ms · claude-haiku-4-5 · $0.0279

      Candidates: Qxc7 (Captures checking knight, wins material decisively, preserves castling rights and piece coordination) | Ke7 (Escapes check, supports e5 pawn and f6 knight, though relinquishes castling for central devel…

      • chess.js.legal_moves0ms
      • llm.candidates49788ms · $0.0279
      full reasoning
      Candidates: Qxc7 (Captures checking knight, wins material decisively, preserves castling rights and piece coordination) | Ke7 (Escapes check, supports e5 pawn and f6 knight, though relinquishes castling for central development) | Kd7 (Escapes check but blocks Nbd7 development, passive response forgoes castling and kingside consolidation goals)
    • 7. Verify0 tok · 1ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect2761 tok · 27293ms · claude-haiku-4-5 · $0.0138

      Final pick: Qxc7 — Captures undefended checking knight on c7, winning material decisively. No piece defends c7. Concrete material gain outweighs any positional concessions.. Rejected: e8e7, e8d7.

      • llm.reflect27293ms · $0.0138
    • 9. Commit0 tok · 0ms

      Commit Qxc7 (d8c7).

  15. 15.Nxd5Opus3.320 tok · $0.2486 · 65931ms
    • 1. Observe0 tok · 0ms

      Halbzug 15, Weiss am Zug. Phase: Eroeffnung. Schwarz +1 Punkte. Legale Zuege: 38. Criticality: 0.40.

      • material-counter0ms
    • 2. Recall Position0 tok · 13ms

      recall: 12 similar position(s) found (limit=15).

      • nex_search13ms
    • 3. Recall Opponent0 tok · 9ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search9ms
    • 4. Research0 tok · 0ms · skipped

      research: opening_explorer + web_search both disabled — pure memory-only opening plan.

    • 5. Plan1594 tok · 29819ms · claude-opus-4-8 · $0.1194

      Phase: opening. Strike the overextended c5-d5-e5 center immediately (capture on d5) to open lines, then use the c3-knight's jump to b5 to hit the early-developed queen on c7 with tempo, regaining the pawn or seizing the …

      • llm.plan29819ms · $0.1194
      full reasoning
      Phase: opening. Strike the overextended c5-d5-e5 center immediately (capture on d5) to open lines, then use the c3-knight's jump to b5 to hit the early-developed queen on c7 with tempo, regaining the pawn or seizing the initiative against Black's king stuck on e8. Punish Black's premature pawn-grab and overextension by liquidating the loose center, exploiting the uncastled king and the exposed Qc7, then complete development and castle short to convert structural/king-safety edges into material. Critical: Black's center (c5/d5/e5) is broad but loose — d5 and e5 become targets once the e4 tension resolves; Black's queen on c7 was developed early (anti-pattern: queen late) and is hittable by Nb5/Nd5 with tempo; Own risk: I am down one pawn and not yet castled, so I must not open the center recklessly while my own king sits on e1 — strike must come with tempo, not loss of time; Black's likely reply is to recapture and consolidate with ...Be7 and ...O-O; if I dawdle the extra pawn plus center solidifies into a stable edge for Black.
    • 6. Candidates508 tok · 14229ms · claude-opus-4-8 · $0.0380

      Candidates: exd5 (Liquidates Black's loose center with tempo, opens lines toward the uncastled king and clears e4 for my pieces.) | Nb5 (Hits the early-developed Qc7 with tempo and eyes d6/c7 forks, punishing the prematu…

      • chess.js.legal_moves0ms
      • llm.candidates14223ms · $0.0380
      full reasoning
      Candidates: exd5 (Liquidates Black's loose center with tempo, opens lines toward the uncastled king and clears e4 for my pieces.) | Nb5 (Hits the early-developed Qc7 with tempo and eyes d6/c7 forks, punishing the premature queen sortie before Black consolidates.) | Nxd5 (Captures a central pawn, attacks Nf6 and Qc7's diagonal, regaining material while exploiting the exposed queen and king on e8.)
    • 7. Verify0 tok · 0ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect1218 tok · 21845ms · claude-opus-4-8 · $0.0912

      Final pick: Nxd5 — Nxd5 forks Qc7 and Nf6 from one square, forcing ...Nxd5 exd5: I regain my pawn immediately, equalize material, and keep a strong central d5 pawn plus open lines against the uncastled king.. Rejected: e…

      • llm.reflect21845ms · $0.0912
      full reasoning
      Final pick: Nxd5 — Nxd5 forks Qc7 and Nf6 from one square, forcing ...Nxd5 exd5: I regain my pawn immediately, equalize material, and keep a strong central d5 pawn plus open lines against the uncastled king.. Rejected: e4d5, c3b5.
    • 9. Commit0 tok · 0ms

      Commit Nxd5 (c3d5).

  16. 16...Qa5+Haiku18.459 tok · $0.0922 · 170054ms
    • 1. Observe0 tok · 0ms

      Halbzug 16, Schwarz am Zug. Phase: Mittelspiel. Material gleich. Legale Zuege: 34. Criticality: 0.15.

      • material-counter0ms
    • 2. Recall Position0 tok · 17ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search17ms
    • 3. Recall Opponent0 tok · 8ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search8ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan5990 tok · 56784ms · claude-haiku-4-5 · $0.0299

      Phase: middlegame. Complete development with Be6 or Nbd7, castle kingside, defend the e5 pawn against Nxe5. Prepare counter-play against Nd5's potential Nc7 jump through piece coordination. Transform underdeveloped posit…

      • llm.plan56784ms · $0.0299
      full reasoning
      Phase: middlegame. Complete development with Be6 or Nbd7, castle kingside, defend the e5 pawn against Nxe5. Prepare counter-play against Nd5's potential Nc7 jump through piece coordination. Transform underdeveloped position into consolidated, balanced middlegame by securing piece development, king safety, and e5 support, then exploit central control for dynamic counterplay. Critical: Nd5 threatens Nc7 deep incursion; e5 pawn vulnerable to Nxe5 capture; Piece development lag (Bc8, Bf8, king uncastled); White's space+initiative from e4+Nd5.
    • 6. Candidates8239 tok · 71776ms · claude-haiku-4-5 · $0.0412

      Candidates: Qa5+ (Check forces tempo, King displaced. Black consolidates with development, Be6, castle. Counters Nd5.) | Nxd5 (Eliminates critical Nd5 before Nc7 incursion. Removes main tactical threat on e5 pawn.) | Nxe…

      • chess.js.legal_moves0ms
      • llm.candidates71775ms · $0.0412
      full reasoning
      Candidates: Qa5+ (Check forces tempo, King displaced. Black consolidates with development, Be6, castle. Counters Nd5.) | Nxd5 (Eliminates critical Nd5 before Nc7 incursion. Removes main tactical threat on e5 pawn.) | Nxe4 (Activates Nf6, removes e4 support pawn. Allows f5 counterplay if White recaptures Qxe4.)
    • 7. Verify0 tok · 0ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect4230 tok · 41448ms · claude-haiku-4-5 · $0.0211

      Final pick: Qa5+ — Check forces King displacement, Black develops with tempo (Be6, O-O). Most forcing move consolidates position.. Rejected: f6d5, f6e4.

      • llm.reflect41448ms · $0.0211
    • 9. Commit0 tok · 0ms

      Commit Qa5+ (c7a5).

  17. 17.Bd2Opus3.025 tok · $0.2265 · 57733ms
    • 1. Observe0 tok · 0ms

      Halbzug 17, Weiss am Zug. Phase: Mittelspiel. Material gleich. Legale Zuege: 7. Schach! Criticality: 0.40.

      • material-counter0ms
    • 2. Recall Position0 tok · 19ms

      recall: 10 similar position(s) found (limit=15).

      • nex_search19ms
    • 3. Recall Opponent0 tok · 6ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search6ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan1371 tok · 25773ms · claude-opus-4-8 · $0.1027

      Phase: middlegame. Answer the Qa5+ check with a developing block that also hits the queen, winning a tempo; keep the dominant d5-knight outpost, finish development of the dark-squared bishop, and castle short to convert …

      • llm.plan25773ms · $0.1027
      full reasoning
      Phase: middlegame. Answer the Qa5+ check with a developing block that also hits the queen, winning a tempo; keep the dominant d5-knight outpost, finish development of the dark-squared bishop, and castle short to convert my lead in coordination against Black's stuck king. Exploit the powerful Nd5 outpost (heuristic: a knight on d5 is extremely hard to dislodge) and Black's uncastled king by developing with tempo against the exposed Qa5, then open lines toward e8 and dominate the central files with my rooks. Critical: Must legally resolve the check first — only blocks/king moves are playable, so a block that simultaneously attacks the queen is ideal (tempo gain); Prophylaxis (memory: always ask what the opponent threatens): Black's queen on the a5-e1 diagonal and possible ...Nxd5 or ...Bb4 pins must be neutralized before I commit; don't allow a queen-for-knight trade that frees Black; Weak-squares/outpost heuristic: preserve Nd5's grip — avoid letting Black play ...Nxd5 exd5 only if it opens the e-file favorably for me; Open-file rook heuristic: after castling, the central e-file and d-file are my rooks' future highways against the king on e8; Avoid greedy queen-side pawn grabs that surrender the initiative; keep pieces coordinated toward the kingside/center where Black is undeveloped.
    • 6. Candidates1406 tok · 23491ms · claude-opus-4-8 · $0.1053

      Candidates: Bd2 (Blocks check on d2 and attacks Qa5 along the diagonal, gaining a tempo while developing the bishop and preserving the Nd5 outpost.) | Qd2 (Blocks and attacks the queen, offering a trade; keeps Nd5 intact…

      • chess.js.legal_moves0ms
      • llm.candidates23490ms · $0.1053
      full reasoning
      Candidates: Bd2 (Blocks check on d2 and attacks Qa5 along the diagonal, gaining a tempo while developing the bishop and preserving the Nd5 outpost.) | Qd2 (Blocks and attacks the queen, offering a trade; keeps Nd5 intact but slightly passive, eases pressure without developing a minor piece.) | c3 (Solid pawn block that secures the diagonal and prepares b4/d4 expansion; no tempo gain but keeps the dominant d5-knight and structure intact.)
    • 7. Verify0 tok · 1ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect248 tok · 8426ms · claude-opus-4-8 · $0.0185

      Final pick: Bd2 — Blocks the check while attacking Qa5 with tempo, develops the bishop, preserves the dominant Nd5 outpost, and prepares castling to dominate the central files against Black's stuck king.. Rejected: d1d2,…

      • llm.reflect8426ms · $0.0185
      full reasoning
      Final pick: Bd2 — Blocks the check while attacking Qa5 with tempo, develops the bishop, preserves the dominant Nd5 outpost, and prepares castling to dominate the central files against Black's stuck king.. Rejected: d1d2, c2c3.
    • 9. Commit0 tok · 0ms

      Commit Bd2 (c1d2).

  18. 18...Nxd5Haiku17.078 tok · $0.0853 · 160648ms
    • 1. Observe0 tok · 0ms

      Halbzug 18, Schwarz am Zug. Phase: Mittelspiel. Material gleich. Legale Zuege: 36. Criticality: 0.25.

      • material-counter0ms
    • 2. Recall Position0 tok · 18ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search18ms
    • 3. Recall Opponent0 tok · 7ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search7ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan3163 tok · 38829ms · claude-haiku-4-5 · $0.0158

      Phase: middlegame. Complete piece development (Be6 or Nbd7), castle kingside within 2 moves, defend e5 against Nxe5, neutralize Nd5 with piece coordination Consolidate king safety and development, then exploit c5 pawn an…

      • llm.plan38829ms · $0.0158
      full reasoning
      Phase: middlegame. Complete piece development (Be6 or Nbd7), castle kingside within 2 moves, defend e5 against Nxe5, neutralize Nd5 with piece coordination Consolidate king safety and development, then exploit c5 pawn and piece coordination for queenside counter-play (b4 expansion) against White's space advantage Critical: e5 undefended vs Nxe5; defend immediately; Nc7+ fork threat if queen repositions carelessly; uncastled king on e8 vulnerable to central tactics; three pieces underdeveloped; completion dictates middlegame dynamics.
    • 6. Candidates11071 tok · 91404ms · claude-haiku-4-5 · $0.0553

      Candidates: Nxd5 (Eliminates White's dangerous Nd5, stops Nxe5 threat, secures e5 pawn. Consolidates position.) | Be6 (Completes piece development, controls center, activates long diagonal, prepares kingside castling.) |…

      • chess.js.legal_moves0ms
      • llm.candidates91402ms · $0.0553
      full reasoning
      Candidates: Nxd5 (Eliminates White's dangerous Nd5, stops Nxe5 threat, secures e5 pawn. Consolidates position.) | Be6 (Completes piece development, controls center, activates long diagonal, prepares kingside castling.) | Qxd2+ (Forcing check, exchanges queens, simplifies position, exposes White's king to center danger.)
    • 7. Verify0 tok · 1ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect2844 tok · 30371ms · claude-haiku-4-5 · $0.0142

      Final pick: Nxd5 — Eliminates the dangerous Nd5 knight immediately. Stops both Nxe5 (winning the e-pawn) and Nc7+ royal fork. Forces simplification on Black's terms. Allows kingside castle next.. Rejected: c8e6, a5d2.

      • llm.reflect30371ms · $0.0142
    • 9. Commit0 tok · 0ms

      Commit Nxd5 (f6d5).

  19. 19.Bxa5Opus5.473 tok · $0.4101 · 94130ms
    • 1. Observe0 tok · 0ms

      Halbzug 19, Weiss am Zug. Phase: Mittelspiel. Schwarz +3 Punkte. Legale Zuege: 31. Criticality: 0.00.

      • material-counter0ms
    • 2. Recall Position0 tok · 13ms

      recall: 10 similar position(s) found (limit=15).

      • nex_search13ms
    • 3. Recall Opponent0 tok · 8ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search8ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan3484 tok · 53375ms · claude-opus-4-8 · $0.2612

      Phase: middlegame. Capture the enemy knight that just occupied its central outpost with my central pawn — it is completely undefended, so the recapture wins back the piece I am temporarily down and equalizes material at …

      • llm.plan53375ms · $0.2612
      full reasoning
      Phase: middlegame. Capture the enemy knight that just occupied its central outpost with my central pawn — it is completely undefended, so the recapture wins back the piece I am temporarily down and equalizes material at a stroke. Then immediately address the pin of my dark-squared bishop to my king before doing anything ambitious (heuristic: prophylaxis — ask what the opponent threatens before executing my own plan). Recover material by eliminating Black's powerful central knight (heuristic: weak-squares/outpost — a strong central knight is hard to dislodge, so remove it now while it hangs), neutralize the diagonal pin and queen pressure, castle the king to safety, and use the half-open central files for my rooks (heuristic: rooks belong on open files) to outcoordinate Black's uncastled king. Critical: My dark-squared bishop is pinned to my king along the long diagonal by the enemy queen — must not lose it for nothing; Opponent threats against b2 and the pinned bishop via queen shifts (e.g. to b4); Any in-between queen capture on the bishop loses the queen for a minor (heuristic: trade favourably when material is at stake), so the recapture is safe; My king is still uncastled — central files could open against me if I delay consolidation; After the recapture, watch a central pawn push by Black aiming to open lines and activate the two bishops.
    • 6. Candidates1717 tok · 31804ms · claude-opus-4-8 · $0.1287

      Candidates: Bxa5 (The diagonal d2-c3-b4-a5 is clear and a5 is undefended; capturing the pinning queen wins it outright for the bishop, decisive material swing.) | exd5 (Recaptures the hanging central knight to equalize m…

      • chess.js.legal_moves0ms
      • llm.candidates31802ms · $0.1287
      full reasoning
      Candidates: Bxa5 (The diagonal d2-c3-b4-a5 is clear and a5 is undefended; capturing the pinning queen wins it outright for the bishop, decisive material swing.) | exd5 (Recaptures the hanging central knight to equalize material if I overlook the queen, but far inferior to taking the queen itself.) | Bb5+ (Developing check pinning ideas, but leaves the queen and material situation unresolved; only a backup if the captures were illegal.)
    • 7. Verify0 tok · 2ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect272 tok · 8906ms · claude-opus-4-8 · $0.0203

      Final pick: Bxa5 — Black's queen on a5 sits undefended on the d2-a5 diagonal; my bishop captures it outright, winning a full queen for nothing. This dwarfs the pawn I am temporarily down and is instantly decisive.. Rejec…

      • llm.reflect8906ms · $0.0203
      full reasoning
      Final pick: Bxa5 — Black's queen on a5 sits undefended on the d2-a5 diagonal; my bishop captures it outright, winning a full queen for nothing. This dwarfs the pawn I am temporarily down and is instantly decisive.. Rejected: e4d5, f1b5.
    • 9. Commit0 tok · 0ms

      Commit Bxa5 (d2a5).

  20. 20...Be6Haiku11.731 tok · $0.0585 · 114883ms
    • 1. Observe0 tok · 1ms

      Halbzug 20, Schwarz am Zug. Phase: Mittelspiel. Weiss +6 Punkte. Legale Zuege: 29. Criticality: 0.00.

      • material-counter0ms
    • 2. Recall Position0 tok · 15ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search15ms
    • 3. Recall Opponent0 tok · 6ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search6ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan2244 tok · 24772ms · claude-haiku-4-5 · $0.0112

      Phase: middlegame. Defend e5 immediately (core weakness vs Nxe5), complete development (Be6 or Nf6/Nbd7), castle kingside within 2 moves. Prepare c5-b4 queenside expansion once king safe. Consolidate king safety and fini…

      • llm.plan24772ms · $0.0112
      full reasoning
      Phase: middlegame. Defend e5 immediately (core weakness vs Nxe5), complete development (Be6 or Nf6/Nbd7), castle kingside within 2 moves. Prepare c5-b4 queenside expansion once king safe. Consolidate king safety and finish development, neutralize White's space advantage, then generate queenside counterattack via c5-b4 against White's loose queenside (Ba5 out of play, a-file weak). Critical: e5 pawn undefended — Nxe5 is material threat and must be addressed immediately via Be6, Nf6, or piece repositioning; Uncastled king on e8 vulnerable to central tactics and discovered attacks (Ba5-Nd5 coordination risk); Three pieces underdeveloped (Be8, Nf8, rook activation) — development lag must close before White's initiative sharpens; Nc7+ fork motif available if White queen or king position carelessly after development completes.
    • 6. Candidates6364 tok · 57292ms · claude-haiku-4-5 · $0.0318

      Candidates: Be6 (Develops bishop to active central square, controls critical center squares, preps kingside castling within next moves.) | Nf6 (Develops knight to control e4, supports center pawns, pressures White positi…

      • chess.js.legal_moves0ms
      • llm.candidates57291ms · $0.0318
      full reasoning
      Candidates: Be6 (Develops bishop to active central square, controls critical center squares, preps kingside castling within next moves.) | Nf6 (Develops knight to control e4, supports center pawns, pressures White position, enables castling kingside soon.) | Bd7 (Develops bishop, supports pawn structure, maintains flexibility, completes first wave of piece development sequence.)
    • 7. Verify0 tok · 0ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect3123 tok · 32783ms · claude-haiku-4-5 · $0.0156

      Final pick: Be6 — Develops bishop to central square and allows Nxe5 recapture if White takes on e5. Defends the core weakness tactically. Prepares kingside castling.. Rejected: d5f6, c8d7.

      • llm.reflect32783ms · $0.0156
    • 9. Commit0 tok · 0ms

      Commit Be6 (c8e6).

  21. 21.exd5Opus2.483 tok · $0.1859 · 52213ms
    • 1. Observe0 tok · 0ms

      Halbzug 21, Weiss am Zug. Phase: Mittelspiel. Weiss +6 Punkte. Legale Zuege: 39. Criticality: 0.10.

      • material-counter0ms
    • 2. Recall Position0 tok · 17ms

      recall: 10 similar position(s) found (limit=15).

      • nex_search17ms
    • 3. Recall Opponent0 tok · 6ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search6ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan1133 tok · 21764ms · claude-opus-4-8 · $0.0849

      Phase: middlegame. Capture the central knight on d5 with my e-pawn, accept the bishop recapture, and convert my queen-for-minor advantage by completing development (castle, activate rooks on the d- and e-files). Liquidat…

      • llm.plan21764ms · $0.0849
      full reasoning
      Phase: middlegame. Capture the central knight on d5 with my e-pawn, accept the bishop recapture, and convert my queen-for-minor advantage by completing development (castle, activate rooks on the d- and e-files). Liquidate Black's only active piece, neutralize the bishop pin on my king via prompt development/castling, then use my extra queen plus heavy pieces on open central files to mount a coordinated attack on the uncastled Black king. Critical: my f1-bishop and king are still undeveloped, so I must castle before pushing; Black's c5/e5 pawns control central squares and his Be6 eyes my queenside; after the recapture watch for tactics against my a5-bishop, which is offside and could become a target (heuristic: bad/offside bishop).
    • 6. Candidates862 tok · 17283ms · claude-opus-4-8 · $0.0645

      Candidates: exd5 (Wins the central knight outright; after Bxd5 I liquidate Black's only active piece and keep my decisive material lead.) | Bb5+ (Develops the last minor with tempo via check, preparing castling next; the…

      • chess.js.legal_moves0ms
      • llm.candidates17279ms · $0.0645
      full reasoning
      Candidates: exd5 (Wins the central knight outright; after Bxd5 I liquidate Black's only active piece and keep my decisive material lead.) | Bb5+ (Develops the last minor with tempo via check, preparing castling next; the d5 knight still falls to e4 afterward.) | Bc4 (Develops bishop, adds a second attacker on d5, and clears f1 so I can finally castle and contest the central files.)
    • 7. Verify0 tok · 0ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect488 tok · 13127ms · claude-opus-4-8 · $0.0365

      Final pick: exd5 — Wins the centralized knight outright. After Bxd5 I trade off Black's only active minor, simplifying toward my overwhelming material lead (queen up) where liquidation is the cleanest conversion.. Reject…

      • llm.reflect13127ms · $0.0365
      full reasoning
      Final pick: exd5 — Wins the centralized knight outright. After Bxd5 I trade off Black's only active minor, simplifying toward my overwhelming material lead (queen up) where liquidation is the cleanest conversion.. Rejected: f1b5, f1c4.
    • 9. Commit0 tok · 0ms

      Commit exd5 (e4d5).

  22. 22...Bxd5Haiku10.852 tok · $0.0542 · 103786ms
    • 1. Observe0 tok · 1ms

      Halbzug 22, Schwarz am Zug. Phase: Mittelspiel. Weiss +9 Punkte. Legale Zuege: 25. Criticality: 0.00.

      • material-counter0ms
    • 2. Recall Position0 tok · 14ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search14ms
    • 3. Recall Opponent0 tok · 5ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search5ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan1734 tok · 22747ms · claude-haiku-4-5 · $0.0086

      Phase: middlegame. Defend e5 immediately (Nf6 covers defender + develops). Castle kingside within 1-2 moves. Complete minor piece development (Nbd7 or Nc6). Lock in king safety as foundation for queenside counterattack v…

      • llm.plan22747ms · $0.0086
      full reasoning
      Phase: middlegame. Defend e5 immediately (Nf6 covers defender + develops). Castle kingside within 1-2 moves. Complete minor piece development (Nbd7 or Nc6). Lock in king safety as foundation for queenside counterattack via c5-b4 against exposed White queenside. After castling and finishing development, exploit White's IQP on d5 as a long-term weakness by c5-b4 pressure, targeting Ba5 and opening queenside files while White's pieces drift passively. Critical: e5 undefended—Nxe5 wins material immediately; Black king uncastled—vulnerable to central tactics and discovered attacks; Ba5 is out of play and vulnerable to tempo tactics after queenside expansion begins.
    • 6. Candidates5858 tok · 49241ms · claude-haiku-4-5 · $0.0293

      Candidates: Bxd5 (Removes White's dangerous advanced d5 pawn, simplifies position, activates the bishop, forces recapture while reducing space advantage.) | e4 (Aggressive pawn advance gains central space, creates tensio…

      • chess.js.legal_moves0ms
      • llm.candidates49239ms · $0.0293
      full reasoning
      Candidates: Bxd5 (Removes White's dangerous advanced d5 pawn, simplifies position, activates the bishop, forces recapture while reducing space advantage.) | e4 (Aggressive pawn advance gains central space, creates tension, supports immediate queenside counterplay despite uncastled king position.) | Rb8 (Develops rook, prepares queenside expansion via c5-c4, supports long-term queenside pressure strategy with b-file activity.)
    • 7. Verify0 tok · 0ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect3260 tok · 31761ms · claude-haiku-4-5 · $0.0163

      Final pick: Bxd5 — Removes White's dangerous advanced d5 pawn, forces simplification via Qxd5, improves bishop placement, reduces White's space advantage and gives Black time to complete development (castle, minor pieces…

      • llm.reflect31761ms · $0.0163
      full reasoning
      Final pick: Bxd5 — Removes White's dangerous advanced d5 pawn, forces simplification via Qxd5, improves bishop placement, reduces White's space advantage and gives Black time to complete development (castle, minor pieces).. Rejected: e5e4, a8b8.
    • 9. Commit0 tok · 0ms

      Commit Bxd5 (e6d5).

  23. 23.Qxd5Opus2.071 tok · $0.1550 · 49044ms
    • 1. Observe0 tok · 0ms

      Halbzug 23, Weiss am Zug. Phase: Mittelspiel. Weiss +8 Punkte. Legale Zuege: 38. Criticality: 0.10.

      • material-counter0ms
    • 2. Recall Position0 tok · 13ms

      recall: 10 similar position(s) found (limit=15).

      • nex_search13ms
    • 3. Recall Opponent0 tok · 6ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search6ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan1039 tok · 20247ms · claude-opus-4-8 · $0.0778

      Phase: middlegame. Kick the active Bd5 with c4, blunt its g2/a2 diagonal, then complete development and castle kingside to tuck the king away before pushing my queen-plus advantage. Convert a full extra queen by neutrali…

      • llm.plan20247ms · $0.0778
      full reasoning
      Phase: middlegame. Kick the active Bd5 with c4, blunt its g2/a2 diagonal, then complete development and castle kingside to tuck the king away before pushing my queen-plus advantage. Convert a full extra queen by neutralizing Black's only active piece, achieving king safety, and seizing the open d-file with coordinated heavy pieces to attack the uncastled Black king. Critical: Bd5 hits g2/a2 and my undeveloped king on e1 — prophylaxis first (memory: prophylaxis, ask 'was droht der Gegner'); my own weakness: f1-bishop blocks the rook, king uncastled; must develop before any push (memory: piece-coordination attack needs 3+ pieces, not a lone queen); open d-file is the conversion lane (memory: Tuerme auf offene Linien); avoid trading my queen, instead simplify Black's minors to kill counterplay.
    • 6. Candidates777 tok · 20282ms · claude-opus-4-8 · $0.0582

      Candidates: Qxd5 (Black's Bd5 is completely undefended (no c6 pawn, no piece covers it) — free bishop wins, removing Black's only active piece and counterplay.) | Bb5+ (Develops with tempo, check forces a king move and p…

      • chess.js.legal_moves0ms
      • llm.candidates20280ms · $0.0582
      full reasoning
      Candidates: Qxd5 (Black's Bd5 is completely undefended (no c6 pawn, no piece covers it) — free bishop wins, removing Black's only active piece and counterplay.) | Bb5+ (Develops with tempo, check forces a king move and prevents castling; but lets Bd5 survive, so inferior to grabbing the piece outright.) | c4 (Prophylactic kick of the active Bd5 per plan, blunting g2/a2 diagonal; sound but slower than simply capturing the loose bishop.)
    • 7. Verify0 tok · 1ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect255 tok · 8473ms · claude-opus-4-8 · $0.0190

      Final pick: Qxd5 — Bd5 is completely undefended (no c6 pawn, no piece covers d5). Qxd5 wins a full bishop for nothing, eliminating Black's only active piece and all counterplay on the g2/a2 diagonal.. Rejected: f1b5, c2c…

      • llm.reflect8473ms · $0.0190
      full reasoning
      Final pick: Qxd5 — Bd5 is completely undefended (no c6 pawn, no piece covers d5). Qxd5 wins a full bishop for nothing, eliminating Black's only active piece and all counterplay on the g2/a2 diagonal.. Rejected: f1b5, c2c4.
    • 9. Commit0 tok · 0ms

      Commit Qxd5 (d1d5).

  24. 24...e4Haiku13.033 tok · $0.0651 · 127031ms
    • 1. Observe0 tok · 0ms

      Halbzug 24, Schwarz am Zug. Phase: Mittelspiel. Weiss +11 Punkte. Legale Zuege: 18. Criticality: 0.00.

      • material-counter0ms
    • 2. Recall Position0 tok · 10ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search10ms
    • 3. Recall Opponent0 tok · 4ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search4ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan3588 tok · 39780ms · claude-haiku-4-5 · $0.0179

      Phase: middlegame. Defend central pawn immediately. Develop remaining minor pieces. Achieve king safety through castling. Then shift to queenside expansion to displace opponent's bishop and activate rooks on semi-open li…

      • llm.plan39780ms · $0.0179
      full reasoning
      Phase: middlegame. Defend central pawn immediately. Develop remaining minor pieces. Achieve king safety through castling. Then shift to queenside expansion to displace opponent's bishop and activate rooks on semi-open lines. After castling and completing development, execute queenside pawn pressure to displace the bishop, control central blockade squares, and build rook activity on partially open files. Critical: Central pawn currently undefended—requires immediate defensive coverage; King remains in center, vulnerable to Queen on d5 and central tactics; Opponent's bishop awkwardly placed on a5—target for future pawn advances; Opponent's initiative is tactical and temporary; solid development neutralizes it.
    • 6. Candidates5157 tok · 47910ms · claude-haiku-4-5 · $0.0257

      Candidates: e4 (Advance central pawn to gain space, remove hanging piece, open lines for queenside activity) | Rb8 (Develop rook to b-file, prepare queenside pawn pressure with b5 to displace bishop) | Rc8 (Activate rook…

      • chess.js.legal_moves0ms
      • llm.candidates47909ms · $0.0257
      full reasoning
      Candidates: e4 (Advance central pawn to gain space, remove hanging piece, open lines for queenside activity) | Rb8 (Develop rook to b-file, prepare queenside pawn pressure with b5 to displace bishop) | Rc8 (Activate rook on semi-open c-file, coordinate queenside expansion and strengthen center control)
    • 7. Verify0 tok · 1ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect4288 tok · 39313ms · claude-haiku-4-5 · $0.0214

      Final pick: e4 — e5 pawn is hanging to Qd5 with no defender. Advancing removes it from immediate capture, gains space, and activates the pawn to d3/f3 control squares.. Rejected: a8b8, a8c8.

      • llm.reflect39313ms · $0.0214
    • 9. Commit0 tok · 0ms

      Commit e4 (e5e4).

  25. 25.Qxe4+Opus2.857 tok · $0.2139 · 56654ms
    • 1. Observe0 tok · 0ms

      Halbzug 25, Weiss am Zug. Phase: Mittelspiel. Weiss +11 Punkte. Legale Zuege: 50. Criticality: 0.10.

      • material-counter0ms
    • 2. Recall Position0 tok · 7ms

      recall: 10 similar position(s) found (limit=15).

      • nex_search7ms
    • 3. Recall Opponent0 tok · 4ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search4ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan763 tok · 15822ms · claude-opus-4-8 · $0.0571

      Phase: middlegame. Consolidate the extra queen: develop the f1-bishop, castle kingside to safety, and centralize rooks on the open d-file behind my dominant Qd5. With a full queen up I must avoid all counterplay, finish …

      • llm.plan15822ms · $0.0571
      full reasoning
      Phase: middlegame. Consolidate the extra queen: develop the f1-bishop, castle kingside to safety, and centralize rooks on the open d-file behind my dominant Qd5. With a full queen up I must avoid all counterplay, finish development and castle, then convert the material edge by trading down or mating the uncastled Black king on the d/e files. Critical: Black's e4 and c5 pawns can advance to gain space or open lines for the rooks; my king is still on e1 and the f1-bishop blocks the h1-rook (memory: prophylaxis, ask 'was droht der Gegner'); Ba5 is loosely placed and could be hit by ...b6; coordinate before pushing (memory: piece coordination attack, open file rooks).
    • 6. Candidates675 tok · 13396ms · claude-opus-4-8 · $0.0505

      Candidates: Qxe4+ (Free central pawn with check, centralizes queen and disrupts Black; consolidates the winning material edge safely.) | Bc4 (Develops bishop eyeing f7, unblocks h1-rook, prepares castling per plan to fin…

      • chess.js.legal_moves0ms
      • llm.candidates13393ms · $0.0505
      full reasoning
      Candidates: Qxe4+ (Free central pawn with check, centralizes queen and disrupts Black; consolidates the winning material edge safely.) | Bc4 (Develops bishop eyeing f7, unblocks h1-rook, prepares castling per plan to finish development before pushing.) | Qxb7 (Grabs another free pawn and hits the a8-rook, increasing material dominance while keeping Black tied down.)
    • 7. Verify0 tok · 0ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect1419 tok · 27402ms · claude-opus-4-8 · $0.1063

      Final pick: Qxe4+ — Free central pawn WITH check: gains material and a tempo, keeps the queen dominant in the center with zero risk, and forces Black to react rather than generate counterplay while I'm a full queen up.. …

      • llm.reflect27402ms · $0.1063
      full reasoning
      Final pick: Qxe4+ — Free central pawn WITH check: gains material and a tempo, keeps the queen dominant in the center with zero risk, and forces Black to react rather than generate counterplay while I'm a full queen up.. Rejected: f1c4, d5b7.
    • 9. Commit0 tok · 0ms

      Commit Qxe4+ (d5e4).

  26. 26...Kd7Haiku10.029 tok · $0.0500 · 102073ms
    • 1. Observe0 tok · 0ms

      Halbzug 26, Schwarz am Zug. Phase: Mittelspiel. Weiss +12 Punkte. Legale Zuege: 2. Schach! Criticality: 0.45.

      • material-counter0ms
    • 2. Recall Position0 tok · 18ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search18ms
    • 3. Recall Opponent0 tok · 5ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search5ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan6823 tok · 63856ms · claude-haiku-4-5 · $0.0341

      Phase: middlegame. Escape check immediately (Kd7 or Be7). King safety is critical. Down Q+2B (–12 points) leaves zero margin. Only hope: activate dormant a8/h8 rooks on open lines and create back-rank tactics. Objectivel…

      • llm.plan63856ms · $0.0341
      full reasoning
      Phase: middlegame. Escape check immediately (Kd7 or Be7). King safety is critical. Down Q+2B (–12 points) leaves zero margin. Only hope: activate dormant a8/h8 rooks on open lines and create back-rank tactics. Objectively losing. Pursue King centralization away from e-file checks, push for simplification or perpetual check, activate rooks before mating net closes. Critical: King in check from Qe4; escape via Kd7 or Be7 (only 2 legal moves); Material deficit Q+2B impossible to recover in middlegame; Rooks (a8/h8) dormant and blocked; back-rank fragility exploitable by White.
    • 6. Candidates2121 tok · 23269ms · claude-haiku-4-5 · $0.0106

      Candidates: Kd7 (King centralizes away from e-file pressure, escapes check actively, prepares rook line.) | Be7 (Blocks check, pins bishop to king. Passive defense; e-file pressure persists on king.)

      • chess.js.legal_moves0ms
      • llm.candidates23269ms · $0.0106
    • 7. Verify0 tok · 0ms

      Alle 2 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect1085 tok · 14906ms · claude-haiku-4-5 · $0.0054

      Final pick: Kd7 — Centralizes king away from e-file pressure, opens rook lines for counterplay. Active escape beats passive block.. Rejected: f8e7.

      • llm.reflect14906ms · $0.0054
    • 9. Commit0 tok · 0ms

      Commit Kd7 (e8d7).

  27. 27.O-O-O+Opus1.850 tok · $0.1383 · 50560ms
    • 1. Observe0 tok · 0ms

      Halbzug 27, Weiss am Zug. Phase: Mittelspiel. Weiss +12 Punkte. Legale Zuege: 52. Criticality: 0.10.

      • material-counter0ms
    • 2. Recall Position0 tok · 18ms

      recall: 10 similar position(s) found (limit=15).

      • nex_search18ms
    • 3. Recall Opponent0 tok · 14ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search14ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan990 tok · 19752ms · claude-opus-4-8 · $0.0740

      Phase: middlegame. Develop the f1-bishop and castle kingside, then seize the open d-file with a rook to harass Black's exposed king on d7 — converting my full-queen advantage without allowing counterplay. Finish developm…

      • llm.plan19752ms · $0.0740
      full reasoning
      Phase: middlegame. Develop the f1-bishop and castle kingside, then seize the open d-file with a rook to harass Black's exposed king on d7 — converting my full-queen advantage without allowing counterplay. Finish development, castle to safety, and coordinate queen plus a d-file rook against the uncastled Black king to force mate or massive material gain. Critical: Black king stuck on d7 on the open d-file is the dominant feature (memory: open-file rooks — a rook on d1 hits the king directly); my own king still on e1 demands prophylaxis before committing pieces (memory: prophylaxis — 'was droht der Gegner', Black's rooks on a8/h8 want open lines); an attack needs 3+ coordinated pieces, so queen + rook + bishop must combine before forcing matters (memory: piece coordination attack); Ba5 is loosely placed and could be hit by ...b6; c5-pawn may advance to open lines.
    • 6. Candidates587 tok · 16865ms · claude-opus-4-8 · $0.0439

      Candidates: O-O-O+ (Castles king to safety AND slams a rook onto the open d-file with check — the dual prophylaxis-plus-attack move the plan demands.) | Rd1+ (Immediately occupies the open d-file with check against the d…

      • chess.js.legal_moves0ms
      • llm.candidates16862ms · $0.0439
      full reasoning
      Candidates: O-O-O+ (Castles king to safety AND slams a rook onto the open d-file with check — the dual prophylaxis-plus-attack move the plan demands.) | Rd1+ (Immediately occupies the open d-file with check against the d7 king; coordinates rook with queen, though leaves my king on e1.) | Qxb7+ (Grabs a second pawn with check, but pulls the queen away from the central attack and ignores king safety; less coordinated than castling.)
    • 7. Verify0 tok · 2ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect273 tok · 13876ms · claude-opus-4-8 · $0.0204

      Final pick: O-O-O+ — One move achieves both plan goals: my king reaches safety on c1 while the rook lands on d1 with check against the d7 king. The pinned d-file becomes a mating highway with zero downside.. Rejected: a1…

      • llm.reflect13876ms · $0.0204
      full reasoning
      Final pick: O-O-O+ — One move achieves both plan goals: my king reaches safety on c1 while the rook lands on d1 with check against the d7 king. The pinned d-file becomes a mating highway with zero downside.. Rejected: a1d1, e4b7.
    • 9. Commit0 tok · 0ms

      Commit O-O-O+ (e1c1).

  28. 28...Bd6Haiku18.874 tok · $0.0943 · 162954ms
    • 1. Observe0 tok · 0ms

      Halbzug 28, Schwarz am Zug. Phase: Mittelspiel. Weiss +12 Punkte. Legale Zuege: 2. Schach! Criticality: 0.45.

      • material-counter0ms
    • 2. Recall Position0 tok · 7ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search7ms
    • 3. Recall Opponent0 tok · 5ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search5ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan11934 tok · 98124ms · claude-haiku-4-5 · $0.0596

      Phase: middlegame. Escape Rd1 check via block (Bd6) or King move. Prep Rook activation on a-file or h-file. Create tactical noise to disrupt White's mating buildup. Simplify toward endgame if possible. Down Q+2B (–12pts)…

      • llm.plan98124ms · $0.0596
      full reasoning
      Phase: middlegame. Escape Rd1 check via block (Bd6) or King move. Prep Rook activation on a-file or h-file. Create tactical noise to disrupt White's mating buildup. Simplify toward endgame if possible. Down Q+2B (–12pts), objectively lost. Only practical try: maximize piece coordination, seek perpetual-check patterns, or force simplifications. White's Ba5 + Qe4 + Rd1 form a tight net; stay off e-file and d-file to avoid discovered attacks. Critical: Rd1 check — must escape or block immediately; Ba5 dominates queenside; Qe4 dominates center/e-file; Rooks on a8/h8 inactive — no open lines yet; King on d7 fragile; Kc7, Kc8, Kc6 safest; Ke-moves lose to Qe4; White has Queen+Rooks+2Bishops vs Rooks+1Bishop — conversion-to-mate is White's realistic goal within 10 moves.
    • 6. Candidates5814 tok · 49805ms · claude-haiku-4-5 · $0.0290

      Candidates: Bd6 (Blocks Rd1 check. Activates bishop from idle f8, centralizes on d6. Prepares rook mobility.) | Kc8 (Safe king escape from check. Retreats to queenside, away from center pressure. Necessary in forcing pos…

      • chess.js.legal_moves0ms
      • llm.candidates49804ms · $0.0290
      full reasoning
      Candidates: Bd6 (Blocks Rd1 check. Activates bishop from idle f8, centralizes on d6. Prepares rook mobility.) | Kc8 (Safe king escape from check. Retreats to queenside, away from center pressure. Necessary in forcing position.)
    • 7. Verify0 tok · 0ms

      Alle 2 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect1126 tok · 15001ms · claude-haiku-4-5 · $0.0056

      Final pick: Bd6 — Blocks Rd1 check while centralizing f8-bishop to active square. Solves forcing threat and improves piece coordination in already-losing position. Activity beats passivity.. Rejected: d7c8.

      • llm.reflect15001ms · $0.0056
    • 9. Commit0 tok · 0ms

      Commit Bd6 (f8d6).

  29. 29.Bb5+Opus2.757 tok · $0.2064 · 57250ms
    • 1. Observe0 tok · 0ms

      Halbzug 29, Weiss am Zug. Phase: Mittelspiel. Weiss +12 Punkte. Legale Zuege: 55. Criticality: 0.10.

      • material-counter0ms
    • 2. Recall Position0 tok · 18ms

      recall: 10 similar position(s) found (limit=15).

      • nex_search18ms
    • 3. Recall Opponent0 tok · 6ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search6ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan883 tok · 19352ms · claude-opus-4-8 · $0.0661

      Phase: middlegame. Activate the f1-bishop (Bc4/Bd3) to add a second attacker against Black's exposed d7-king, keep the Rd1 hammering the open d-file, and pry open lines with c4 or a queen infiltration to convert my full-…

      • llm.plan19352ms · $0.0661
      full reasoning
      Phase: middlegame. Activate the f1-bishop (Bc4/Bd3) to add a second attacker against Black's exposed d7-king, keep the Rd1 hammering the open d-file, and pry open lines with c4 or a queen infiltration to convert my full-piece advantage. Coordinate queen, both rooks and the light bishop against the uncastled king on the open d-file to force decisive material gain or mate, trading heavy pieces only when it accelerates the win. Critical: Black's king on d7 sits on the open d-file behind a pinned Bd6 — the dominant target (memory: open-file rooks + piece-coordination-attack: 3 pieces before committing); my own king is already safe on c1, so I can attack freely without prophylaxis cost (memory: prophylaxis — 'was droht der Gegner?' answer: little counterplay with +12); Black's c5/Bd6 cluster and undefended b7 are concrete weaknesses; up material I should also welcome heavy-piece trades that reduce any swindle chances (memory: exchange heavy pieces when conversion is clean).
    • 6. Candidates702 tok · 15432ms · claude-opus-4-8 · $0.0525

      Candidates: Rxd6+ (Removes the pinned defender with check; after Kxd6, Qd4+/Bb4+ skewers king and wins more, exploiting open d-file and 3-piece coordination.) | Bb5+ (Activates the light bishop as second attacker against…

      • chess.js.legal_moves0ms
      • llm.candidates15429ms · $0.0525
      full reasoning
      Candidates: Rxd6+ (Removes the pinned defender with check; after Kxd6, Qd4+/Bb4+ skewers king and wins more, exploiting open d-file and 3-piece coordination.) | Bb5+ (Activates the light bishop as second attacker against d7-king before committing rook; forces awkward king move, then Rxd6+ crashes through.) | Qxb7+ (Grabs undefended b7 with check, increasing material while keeping initiative on the exposed king; clean conversion up heavy material.)
    • 7. Verify0 tok · 2ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect1172 tok · 22416ms · claude-opus-4-8 · $0.0878

      Final pick: Bb5+ — Develops the last piece with tempo, adding a third attacker (Q, Rd1, B) against the d7-king before committing. After the forced king move, Rxd6+ crashes through while I keep all my material advantage i…

      • llm.reflect22416ms · $0.0878
      full reasoning
      Final pick: Bb5+ — Develops the last piece with tempo, adding a third attacker (Q, Rd1, B) against the d7-king before committing. After the forced king move, Rxd6+ crashes through while I keep all my material advantage intact.. Rejected: d1d6, e4b7.
    • 9. Commit0 tok · 0ms

      Commit Bb5+ (f1b5).

  30. 30...Kc8Haiku9.571 tok · $0.0478 · 101063ms
    • 1. Observe0 tok · 0ms

      Halbzug 30, Schwarz am Zug. Phase: Mittelspiel. Weiss +12 Punkte. Legale Zuege: 1. Schach! Criticality: 0.55. AUFGABE empfohlen (Material-Floor).

      • material-counter0ms
    • 2. Recall Position0 tok · 16ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search16ms
    • 3. Recall Opponent0 tok · 11ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search11ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan4197 tok · 51778ms · claude-haiku-4-5 · $0.0209

      Phase: middlegame. Ra1+ forces White king to b2 or d2. Follow with second-rook activation (likely Rh1) to create perpetual-check threats on back rank. Objectively lost (-12 material). Only practical chance: perpetual che…

      • llm.plan51778ms · $0.0209
      full reasoning
      Phase: middlegame. Ra1+ forces White king to b2 or d2. Follow with second-rook activation (likely Rh1) to create perpetual-check threats on back rank. Objectively lost (-12 material). Only practical chance: perpetual check via coordinated rook activity on a/h files before White consolidates Q+2B advantage. Critical: Ra1+ is forcing move (king must abandon c1, weakening back rank); After Kb2, Black has Rh1 threatening back-rank complications; Material deficit -12 leaves zero margin—must find perpetual or resign; White's Qe4+Ba5+Bb5+Rd1 will dominate if Black cannot maintain rook initiative.
    • 6. Candidates5374 tok · 49245ms · claude-haiku-4-5 · $0.0268

      Candidates: Kc8 (Forced: king in check from Bb5, no blocks or captures. Kc8 only escape square.)

      • chess.js.legal_moves0ms
      • llm.candidates49245ms · $0.0268
    • 7. Verify0 tok · 0ms

      Alle 1 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect0 tok · 0ms

      Final pick: Kc8 — Forced: king in check from Bb5, no blocks or captures. Kc8 only escape square.. Rejected: —.

    • 9. Commit0 tok · 0ms

      Commit Kc8 (d7c8).

  31. 31.Rxd6Opus3.085 tok · $0.2310 · 61136ms
    • 1. Observe0 tok · 0ms

      Halbzug 31, Weiss am Zug. Phase: Mittelspiel. Weiss +12 Punkte. Legale Zuege: 63. Criticality: 0.20.

      • material-counter0ms
    • 2. Recall Position0 tok · 11ms

      recall: 10 similar position(s) found (limit=15).

      • nex_search11ms
    • 3. Recall Opponent0 tok · 8ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search8ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan783 tok · 16897ms · claude-opus-4-8 · $0.0586

      Phase: middlegame. Coordinate Qe4, both bishops and Rd1 against Black's exposed c8-king and loose b7/a7 pawns, opening the c- or d-file to force decisive material gain while staying up a full piece. Convert the clean ext…

      • llm.plan16897ms · $0.0586
      full reasoning
      Phase: middlegame. Coordinate Qe4, both bishops and Rd1 against Black's exposed c8-king and loose b7/a7 pawns, opening the c- or d-file to force decisive material gain while staying up a full piece. Convert the clean extra-piece advantage by pressing the uncastled king on the open d-file with three coordinated attackers (memory: piece-coordination-attack needs 3 pieces; open-file rooks), trading heavy pieces only when it speeds mate or simplifies into a trivially won endgame. Critical: Black may try ...Bxa5 to trade a bishop and relieve queenside pressure; my king on c1 sits on the same side as my attack — watch ...c4 or rook lifts to the c-file before overextending (memory: prophylaxis); b7/a7 pawns and the b5/a5 bishop battery create concrete threats around c8; ensure no back-rank or ...Rd8 counter undermines Rd1.
    • 6. Candidates1882 tok · 31320ms · claude-opus-4-8 · $0.1410

      Candidates: Rxd6 (Wins a second clean piece: the d6-bishop is undefended (c5-pawn doesn't cover it). Open d-file rook aligns on the exposed c8-king.) | Qd5 (Centralizes the queen, hits f7 and supports a future d-file inv…

      • chess.js.legal_moves0ms
      • llm.candidates31307ms · $0.1410
      full reasoning
      Candidates: Rxd6 (Wins a second clean piece: the d6-bishop is undefended (c5-pawn doesn't cover it). Open d-file rook aligns on the exposed c8-king.) | Qd5 (Centralizes the queen, hits f7 and supports a future d-file invasion while keeping all three attackers coordinated against c8.) | Bb4 (Re-routes to attack the loose d6-bishop and c5-pawn, adding a third coordinated attacker before the king can flee or untangle.)
    • 7. Verify0 tok · 2ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect420 tok · 12884ms · claude-opus-4-8 · $0.0314

      Final pick: Rxd6 — The d6-bishop is completely undefended (the c5-pawn covers b4/d4, not d6), so Rxd6 simply grabs a second clean piece while the rook lands on the open d-file pointing at the c8-king. Decisive material..…

      • llm.reflect12884ms · $0.0314
      full reasoning
      Final pick: Rxd6 — The d6-bishop is completely undefended (the c5-pawn covers b4/d4, not d6), so Rxd6 simply grabs a second clean piece while the rook lands on the open d-file pointing at the c8-king. Decisive material.. Rejected: e4d5, a5b4.
    • 9. Commit0 tok · 0ms

      Commit Rxd6 (d1d6).

  32. 32...c4Haiku12.268 tok · $0.0612 · 121872ms
    • 1. Observe0 tok · 0ms

      Halbzug 32, Schwarz am Zug. Phase: Mittelspiel. Weiss +15 Punkte. Legale Zuege: 15. Criticality: 0.10. AUFGABE empfohlen (Material-Floor).

      • material-counter0ms
    • 2. Recall Position0 tok · 19ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search19ms
    • 3. Recall Opponent0 tok · 12ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search12ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan2139 tok · 23265ms · claude-haiku-4-5 · $0.0107

      Phase: middlegame. Ra1+ forces White king to b2 or d2, weakening back rank. Follow with Rh1 to threaten back-rank mate. Coordinate rooks on a/h files for perpetual-check threats before White's Q+2B advantage becomes deci…

      • llm.plan23265ms · $0.0107
      full reasoning
      Phase: middlegame. Ra1+ forces White king to b2 or d2, weakening back rank. Follow with Rh1 to threaten back-rank mate. Coordinate rooks on a/h files for perpetual-check threats before White's Q+2B advantage becomes decisive. Objectively lost (-15 material); only practical chance is perpetual check via rook coordination on a1/h1 before White consolidates. Critical: Ra1+ is forcing move that must be played—only way to maintain initiative; White king on c1 vulnerable to back-rank threats after forced king move; After Ra1+ Kb2/Kd2, Rh1 must follow immediately; no time for slow moves with 15-point deficit.
    • 6. Candidates3603 tok · 33243ms · claude-haiku-4-5 · $0.0180

      Candidates: f6 (Attacks d6 rook, forces relocation. Most forcing move available given pawn structure blocks Ra1.) | Rd8 (Activates h-rook with tempo against centralized rook. Creates d-file tension.) | c4 (Advances count…

      • chess.js.legal_moves0ms
      • llm.candidates33242ms · $0.0180
      full reasoning
      Candidates: f6 (Attacks d6 rook, forces relocation. Most forcing move available given pawn structure blocks Ra1.) | Rd8 (Activates h-rook with tempo against centralized rook. Creates d-file tension.) | c4 (Advances counterplay pawn toward promotion line. Sole concrete threat when perpetual check blocked by pawns.)
    • 7. Verify0 tok · 0ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect6526 tok · 65317ms · claude-haiku-4-5 · $0.0326

      Final pick: c4 — Creates concrete passed-pawn threat forcing Qxc4, then Ra1+ becomes immediately available. Only forcing counterplay that both sustains initiative and enables perpetual-check plan.. Rejected: f7f6, h8d8.

      • llm.reflect65316ms · $0.0326
    • 9. Commit0 tok · 0ms

      Commit c4 (c5c4).

  33. 33.Rd8+Opus5.578 tok · $0.4180 · 96866ms
    • 1. Observe0 tok · 0ms

      Halbzug 33, Weiss am Zug. Phase: Mittelspiel. Weiss +15 Punkte. Legale Zuege: 65. Criticality: 0.20.

      • material-counter0ms
    • 2. Recall Position0 tok · 7ms

      recall: 10 similar position(s) found (limit=15).

      • nex_search7ms
    • 3. Recall Opponent0 tok · 5ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search5ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan776 tok · 19745ms · claude-opus-4-8 · $0.0581

      Phase: middlegame. Exploit the stranded c8-king: keep Rd6, both bishops and Qe4 converging on the c-/d-files and the a4-e8 and a6-c8 diagonals to engineer a forced mating net or win further material, never releasing the …

      • llm.plan19745ms · $0.0581
      full reasoning
      Phase: middlegame. Exploit the stranded c8-king: keep Rd6, both bishops and Qe4 converging on the c-/d-files and the a4-e8 and a6-c8 diagonals to engineer a forced mating net or win further material, never releasing the bind. Up a full piece with the enemy king trapped in the center, force mate via maximum coordination (memory: piece-coordination-attack needs 3+ harmonized attackers; open/half-open-file rooks dominate) rather than drifting into a slow technical conversion. Critical: Black's only counterplay is the passed c4-pawn and trades like ...Bxa5/...Rd8 to peel off an attacker — refuse trades that reduce my attacking force; my own Kc1 sits near the open lines, so check Black has no ...Rd8/...Qless cheapo before committing; watch that any rook lift or Ba6/Qe6+ idea stays sound and doesn't allow ...Kb8 escape with consolidation.
    • 6. Candidates3494 tok · 52800ms · claude-opus-4-8 · $0.2619

      Candidates: Rd8+ (Protected by Ba5; forces Kb8, then Qe5+ is mate. Only defense Rhxd8 Bxd8 keeps a crushing, winning bind.) | Qe6+ (Drives king to b8 (c7/d7/d8 all covered by bishops), tightening the net before Rd8 lands…

      • chess.js.legal_moves0ms
      • llm.candidates52788ms · $0.2619
      full reasoning
      Candidates: Rd8+ (Protected by Ba5; forces Kb8, then Qe5+ is mate. Only defense Rhxd8 Bxd8 keeps a crushing, winning bind.) | Qe6+ (Drives king to b8 (c7/d7/d8 all covered by bishops), tightening the net before Rd8 lands without ...Rxd8 resource.) | Qxc4+ (Check that snaps off Black's only counterplay, the passed c-pawn, keeping all attackers while king stays trapped.)
    • 7. Verify0 tok · 1ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect1308 tok · 24297ms · claude-opus-4-8 · $0.0980

      Final pick: Rd8+ — Ba5 protects d8, so Kb8 is forced (c7/c8 covered), then Qe5+ is mate on the e5-b8 diagonal with no block or capture. If Rhxd8 Bxd8 I keep a winning bind, up a piece.. Rejected: e4e6, e4c4.

      • llm.reflect24297ms · $0.0980
    • 9. Commit0 tok · 0ms

      Commit Rd8+ (d6d8).

  34. 34...Rxd8Haiku4.431 tok · $0.0221 · 49571ms
    • 1. Observe0 tok · 0ms

      Halbzug 34, Schwarz am Zug. Phase: Mittelspiel. Weiss +15 Punkte. Legale Zuege: 1. Schach! Criticality: 0.55. AUFGABE empfohlen (Material-Floor).

      • material-counter0ms
    • 2. Recall Position0 tok · 23ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search23ms
    • 3. Recall Opponent0 tok · 17ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search17ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan1707 tok · 21761ms · claude-haiku-4-5 · $0.0085

      Phase: middlegame. Force White king to b2/d2 via check. Follow with Rh1 to create back-rank threats. Coordinate rooks on a/h files for perpetual check opportunities. Maintain forcing sequence before White consolidates 15…

      • llm.plan21761ms · $0.0085
      full reasoning
      Phase: middlegame. Force White king to b2/d2 via check. Follow with Rh1 to create back-rank threats. Coordinate rooks on a/h files for perpetual check opportunities. Maintain forcing sequence before White consolidates 15-point material advantage. Force perpetual checks via rook coordination and back-rank threats until draw or escape from losing position becomes forced. Critical: White king on c1 vulnerable after forced move, back rank weakened; Ra1+ is only forcing move maintaining initiative; must follow with Rh1 immediately; 15-point material deficit means quiet position = loss; only perpetual check tactics work; Time critical—each move must maintain forcing threats or White's Q+2B takes over.
    • 6. Candidates2724 tok · 27752ms · claude-haiku-4-5 · $0.0136

      Candidates: Rxd8 (Forced. Kc8 checked by Rd8. Recapture eliminates White rook, reduces material deficit.)

      • chess.js.legal_moves0ms
      • llm.candidates27752ms · $0.0136
    • 7. Verify0 tok · 1ms

      Alle 1 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect0 tok · 1ms

      Final pick: Rxd8 — Forced. Kc8 checked by Rd8. Recapture eliminates White rook, reduces material deficit.. Rejected: —.

    • 9. Commit0 tok · 0ms

      Commit Rxd8 (h8d8).

  35. 35.Qxc4+Opus3.893 tok · $0.2916 · 71101ms
    • 1. Observe0 tok · 0ms

      Halbzug 35, Weiss am Zug. Phase: Mittelspiel. Weiss +10 Punkte. Legale Zuege: 49. Criticality: 0.20.

      • material-counter0ms
    • 2. Recall Position0 tok · 19ms

      recall: 10 similar position(s) found (limit=15).

      • nex_search19ms
    • 3. Recall Opponent0 tok · 8ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search8ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan925 tok · 19475ms · claude-opus-4-8 · $0.0693

      Phase: middlegame. Convert the trapped c8-king into mate or decisive material: activate Rh1 to the d/e-file, keep Bb5 nailing e8/d7 and Ba5 covering the d8-rook's escape, and use Qe4 to probe e6/e8 and a8 so Black's rook…

      • llm.plan19475ms · $0.0693
      full reasoning
      Phase: middlegame. Convert the trapped c8-king into mate or decisive material: activate Rh1 to the d/e-file, keep Bb5 nailing e8/d7 and Ba5 covering the d8-rook's escape, and use Qe4 to probe e6/e8 and a8 so Black's rooks stay tied down. Up a full piece with the enemy king stuck in the center, force the issue with maximum coordination (Qe4 + both bishops + the rook) to deliver mate rather than drift into slow technique. Critical: Black's only resources are the passed c4-pawn and tempo-gaining hits like ...a6 on Bb5 or rook trades to peel off an attacker; ensure my own king on c1 stays safe from ...Rd8-d1 or ...c3 break ideas before committing; avoid premature checks that let the king run via d7; keep the net intact (per piece-coordination heuristic, need 3+ harmonized attackers).
    • 6. Candidates2030 tok · 34286ms · claude-opus-4-8 · $0.1521

      Candidates: Qxc4+ (Eliminates Black's only counterplay (the passed c4-pawn) with check, keeps queen central; king flees to b8 and I stay up a clean piece.) | Rd1 (Activates the last piece per the plan, contests the d-fil…

      • chess.js.legal_moves0ms
      • llm.candidates34277ms · $0.1521
      full reasoning
      Candidates: Qxc4+ (Eliminates Black's only counterplay (the passed c4-pawn) with check, keeps queen central; king flees to b8 and I stay up a clean piece.) | Rd1 (Activates the last piece per the plan, contests the d-file and pressures the pinned d8-rook while king stays safe on c1.) | Bxc4 (Removes the dangerous c-pawn while preserving the queen for the mating net; bishop stays active eyeing e6/a6.)
    • 7. Verify0 tok · 2ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect938 tok · 17282ms · claude-opus-4-8 · $0.0702

      Final pick: Qxc4+ — Removes Black's only counterplay (the passed c4-pawn) with tempo via check; queen stays central, both bishops keep the c8-king boxed, and I remain a clean piece up with the initiative.. Rejected: h1d1…

      • llm.reflect17282ms · $0.0702
      full reasoning
      Final pick: Qxc4+ — Removes Black's only counterplay (the passed c4-pawn) with tempo via check; queen stays central, both bishops keep the c8-king boxed, and I remain a clean piece up with the initiative.. Rejected: h1d1, b5c4.
    • 9. Commit0 tok · 0ms

      Commit Qxc4+ (e4c4).

  36. 36...Kb8Haiku5.954 tok · $0.0297 · 60091ms
    • 1. Observe0 tok · 0ms

      Halbzug 36, Schwarz am Zug. Phase: Mittelspiel. Weiss +11 Punkte. Legale Zuege: 1. Schach! Criticality: 0.55. AUFGABE empfohlen (Material-Floor).

      • material-counter0ms
    • 2. Recall Position0 tok · 20ms

      recall: 5 similar position(s) found (limit=5).

      • nex_search20ms
    • 3. Recall Opponent0 tok · 15ms

      No pattern found for chess-opus-tm (tag=chess-opus-tm) — mandatory run documented.

      • nex_entity_search15ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan1690 tok · 21246ms · claude-haiku-4-5 · $0.0084

      Phase: middlegame. Ra1+ forces Kd2/Kb1, immediately follow with Rh1 to double-threaten back rank and king. Maintain perpetual check cycle via rook coordination on a- and h-files. Any quiet move is loss—forcing play is on…

      • llm.plan21246ms · $0.0084
      full reasoning
      Phase: middlegame. Ra1+ forces Kd2/Kb1, immediately follow with Rh1 to double-threaten back rank and king. Maintain perpetual check cycle via rook coordination on a- and h-files. Any quiet move is loss—forcing play is only survival. Coordinate Black's only asset (two rooks) to perpetuate checks and back-rank threats against exposed Kc1, forcing a draw through perpetual or fortress since White's 11-point material advantage ends all quiet resistance. Critical: White King c1 cannot escape to safe squares—only Kd2 or Kb1, both still under fire; Back rank (1st rank) is second weakness—Rh1 creates immediate threat after Ra1+ drives king forward; Material deficit is so steep (−11) that this is Black's only path—one quiet move and position collapses; Rook coordination depends on immediate follow-up; cannot afford tempo loss between Ra1+ and Rh1; White's Queen and Bishops become irrelevant once forced into perpetual check pattern.
    • 6. Candidates4264 tok · 38794ms · claude-haiku-4-5 · $0.0213

      Candidates: Kb8 (Forced only legal move—King in check from Qc4. Moves to safety. Positions for future rook coordination on back rank.)

      • chess.js.legal_moves0ms
      • llm.candidates38793ms · $0.0213
    • 7. Verify0 tok · 0ms

      Alle 1 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect0 tok · 0ms

      Final pick: Kb8 — Forced only legal move—King in check from Qc4. Moves to safety. Positions for future rook coordination on back rank.. Rejected: —.

    • 9. Commit0 tok · 0ms

      Commit Kb8 (c8b8).

  37. 37.Qc7#Opus1.880 tok · $0.1406 · 44366ms
    • 1. Observe0 tok · 0ms

      Halbzug 37, Weiss am Zug. Phase: Mittelspiel. Weiss +11 Punkte. Legale Zuege: 47. Criticality: 0.20.

      • material-counter0ms
    • 2. Recall Position0 tok · 20ms

      recall: 10 similar position(s) found (limit=15).

      • nex_search20ms
    • 3. Recall Opponent0 tok · 7ms

      No pattern found for chess-haiku-tm (tag=chess-haiku-tm) — mandatory run documented.

      • nex_entity_search7ms
    • 4. Research0 tok · 0ms · skipped

      middlegame/endgame — research not relevant when both tools off.

    • 5. Plan1115 tok · 21786ms · claude-opus-4-8 · $0.0835

      Phase: middlegame. Seize the d-file with Rd1 to stack on the d8-rook (already hit by Ba5), keep Bb5 cutting the king's escape squares, and use Qc4 to bind c7/f7 so Black cannot untangle the a8/d8 rooks. Up a full piece, …

      • llm.plan21786ms · $0.0835
      full reasoning
      Phase: middlegame. Seize the d-file with Rd1 to stack on the d8-rook (already hit by Ba5), keep Bb5 cutting the king's escape squares, and use Qc4 to bind c7/f7 so Black cannot untangle the a8/d8 rooks. Up a full piece, trade into a winning endgame by overloading the pinned d8-rook and the boxed-in b8-king, converting coordination of Rh1 + both bishops + queen into decisive material or mate. Critical: Black's only counterplay is the passed c4-square pawn break and tempo hits ...a6/...b6 kicking my bishops; must keep Bb5 and Ba5 defended/retreatable so a rook trade doesn't loosen the bind; my Kc1 stays safe — no back-rank or ...Rd1+ tricks since I control d1 after Rd1.
    • 6. Candidates549 tok · 12973ms · claude-opus-4-8 · $0.0411

      Candidates: Qc7# (Checkmate. Qc7 is defended by Ba5; king on b8 has no flight (a8 own rook, c8 covered, b7 pawn). Game over.) | Qc8+ (Forcing check dragging the king or winning the d8-rook, but strictly worse than the im…

      • chess.js.legal_moves0ms
      • llm.candidates12971ms · $0.0411
      full reasoning
      Candidates: Qc7# (Checkmate. Qc7 is defended by Ba5; king on b8 has no flight (a8 own rook, c8 covered, b7 pawn). Game over.) | Qc8+ (Forcing check dragging the king or winning the d8-rook, but strictly worse than the immediate mate.) | Bxd8 (Wins the exchange/full rook cleanly, but ignores the available forced mate.)
    • 7. Verify0 tok · 0ms

      Alle 3 Kandidaten legal. cloud_eval disabled (default).

      • chess.js.legal_recheck0ms
    • 8. Reflect216 tok · 9562ms · claude-opus-4-8 · $0.0161

      Final pick: Qc7# — Checkmate. Qc7 is protected by Ba5, and the b8-king has zero flight squares: a8 holds own rook, c8/c7 covered by queen, b7 own pawn. Immediate game over.. Rejected: c4c8, a5d8.

      • llm.reflect9562ms · $0.0161
    • 9. Commit0 tok · 0ms

      Commit Qc7# (c4c7).

PGN

PGN anzeigen
[Event "Tournament Pairing 2"]
[Site "?"]
[Date "2026-05-31"]
[Round "?"]
[White "chess-opus-tm"]
[Black "chess-haiku-tm"]
[Result "*"]

1. e4 c5 2. Nf3 Nf6 3. Nc3 Nc6 4. d4 Nxd4 5. Nxd4 e5 6. Ndb5 d5 7. Nc7+ Qxc7 8. Nxd5 Qa5+ 9. Bd2 Nxd5 10. Bxa5 Be6 11. exd5 Bxd5 12. Qxd5 e4 13. Qxe4+ Kd7 14. O-O-O+ Bd6 15. Bb5+ Kc8 16. Rxd6 c4 17. Rd8+ Rxd8 18. Qxc4+ Kb8 19. Qc7# *