{"uid":"cap_FW7uebAFF3fmgHwxGoi1_","slug":"chess-best-move-x402-api-b37e9158","name":"Chess Best Move x402 API","description":"Get stockfish analysis for a given FEN","url":"https://chess.ruliad.xyz/best-move","method":"GET","headers":{},"bodySchema":{"type":"object","required":["fen"],"properties":{"fen":{"type":"string","description":"FEN of the current chess position"},"depth":{"type":"string","description":"depth (1-12), optional, default 10"}}},"responseSchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["success","evaluation","bestmove","mate"],"properties":{"mate":{"anyOf":[{"type":"number"},{"type":"null"}]},"success":{"type":"boolean","const":true},"bestmove":{"type":"string"},"evaluation":{"type":"number"}},"additionalProperties":false},"example":{"request":{"fen":"rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 0 1","depth":"10"},"response":{"mate":null,"success":true,"bestmove":"bestmove e7e5 ponder g1f3","evaluation":0.52}},"exampleRequest":{"fen":"rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 0 1","depth":"10"},"tags":["x402"],"displayCostAmount":"0.001","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"settled","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":"$0.001/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_mCVrK3fKr2AvhcnLIph5L","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.001","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns the Stockfish engine's best move and evaluation score for a given chess position in FEN notation","exampleAgentPrompt":"What's the best move for this chess position: 'rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 0 1'? Use depth 12 for the analysis.","exampleUseCases":null,"resultDescription":"A JSON object containing: 'bestmove' (the recommended move in UCI notation, e.g. 'e2e4'), 'evaluation' (a numeric centipawn score from White's perspective), 'mate' (number of moves to forced checkmate if applicable, otherwise null), and 'success' (boolean true).","failureModes":["Invalid FEN string returns an error or unexpected result","Depth out of range (outside 1-12) may be clamped or rejected","Malformed request missing required 'fen' parameter returns 400","Payment not provided or insufficient results in 402 Payment Required","Server overload may cause slow or failed analysis at high depths"],"whenToPreferThis":"Use this endpoint when you need fast, accurate Stockfish-powered chess move analysis for any board position described by a FEN string. It is ideal for building chess assistants, training tools, game analysis pipelines, or evaluating positions programmatically. Prefer this over manual engines when you need pay-per-use pricing via x402 without API key management.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T00:33:34.861Z","isFirstParty":false}