{"uid":"cap_h4z-aLtiwUJ8htOyyNUBT","slug":"chess-position-analysis-move-generation-x402-forgemesh-io-bc27e01d","name":"Chess Position Analysis & Move Generation (x402.forgemesh.io)","description":"Chess position analysis from a FEN string: every legal move in SAN and UCI notation, whose turn it is, and full game-state flags — check, checkmate, stalemate, draw, insufficient material, threefold repetition. Optionally validate and apply one move to get the resulting FEN. Deterministic rules logic, not engine evaluation.","url":"https://x402.forgemesh.io/chess-moves","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"fen":{"type":"string","description":"FEN position string, or 'start' for the initial position"},"move":{"type":"string","description":"Optional move to validate/apply, SAN (Nf3) or UCI (g1f3)"}}},"responseSchema":{"type":"json","example":{"turn":"white","state":{"in_check":false,"game_over":false},"valid_fen":true,"legal_moves":["a3","a4","Nf3"],"move_applied":{"san":"e4","legal":true,"fen_after":"rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq - 0 1"}}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.002","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.002/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_iPz2mQFNHhrvu_OSndFYI","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.002","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Analyzes a chess position from a FEN string, returning all legal moves in SAN and UCI notation, game state flags (check, checkmate, stalemate, draw, etc.), and optionally validates/applies a move to produce the resulting FEN.","exampleAgentPrompt":"What are all the legal moves from this chess position — rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 0 1 — and is the position in check? Also apply the move e7e5 and give me the resulting FEN.","exampleUseCases":null,"resultDescription":"Returns a list of all legal moves in both SAN (e.g. Nf3) and UCI (e.g. g1f3) notation, indicates whose turn it is, and provides boolean game-state flags for check, checkmate, stalemate, draw, insufficient material, and threefold repetition. If a move was provided, also returns the resulting FEN after that move is applied.","failureModes":["Invalid FEN string returns an error indicating unparseable position","Illegal or malformed move string returns a validation error","Move provided is not legal in the given position — returns error indicating illegal move","Missing 'fen' field returns a 400-level bad request","Ambiguous SAN move without sufficient context may fail to parse"],"whenToPreferThis":"Choose this endpoint when you need deterministic rules-based chess move generation or position validation — not engine evaluation or best-move suggestions. Ideal for chess apps, puzzle validators, game state machines, or any workflow that needs to enumerate legal moves or detect terminal game states from a FEN string without calling a full chess engine.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T01:06:41.521Z","isFirstParty":false}