{"slug": "chessigma-api", "title": "Chessigma API", "summary": "Chessigma released version 1.0.0 of its public chess analysis API, a free interface at https://www.chessigma.com/public-api/v1 that requires no API key, signup, or paywall. The API offers four endpoints — /game to submit a PGN for analysis, /game/{gameId} to retrieve analysis, /elo-calculator for Elo rating arithmetic, and /daily-puzzle for one daily puzzle — under a shared global rate limit that returns HTTP 429 when exceeded, with engine analysis running client-side in the browser. Chessigma also published machine-readable discovery files for AI agents, including an OpenAPI 3.1 spec at /openapi.json, an RFC 9727 catalog at /.well-known/api-catalog, an agent skill index at /.well-known/agent-skills/index.json, and an llms.txt documentation index.", "body_md": "For AI agents: the documentation index is at https://www.chessigma.com/llms.txt, and this page is available as Markdown at https://www.chessigma.com/developers.md.\n\nv1.0.0\nA free API for chess game analysis. Submit a game, read its analysis, calculate rating changes, and fetch the daily puzzle. No API key, no signup, no paywall.\n\nBase URL`https://www.chessigma.com/public-api/v1`\n\nNo API key or account. Every endpoint is open.\n\nA shared global limit. Over it returns 429.\n\nEngine analysis runs in the browser. Submit a game, then open its URL to analyze.\n\nPlease attribute Chessigma when you use the API. By using it you accept the [terms of service](https://www.chessigma.com/tos).\n\nSubmit a game, then open the returned URL to view and analyze it.\n\n```\ncurl -X POST https://www.chessigma.com/public-api/v1/game \\\n  -H \"Content-Type: application/json\" \\\n  -d '{\"pgn\": \"[White \\\"Alice\\\"]\\n[Black \\\"Bob\\\"]\\n[Result \\\"1-0\\\"]\\n\\n1. e4 e5 2. Nf3 Nc6 1-0\"}'\n\n# 201 Created\n# { \"gameId\": \"f222a278-...\", \"url\": \"https://www.chessigma.com/games/f222a278-...\", \"status\": \"submitted\" }\n```\n\n`/game`\nSubmit a game (PGN) for analysis\n\nStores a chess game and returns a URL to view and analyze it on Chessigma. Duplicate games (same players + date) are deduplicated and return the existing gameId.\n\n`/game/{gameId}`\nRetrieve analysis for a submitted game\n\nReturns game metadata and analysis. Because analysis runs client-side, this returns data only if a user has already opened the game page and triggered analysis. Only games submitted via this public API are readable here.\n\n`/elo-calculator`\nCompute an Elo rating change for a single game\n\nPure arithmetic. Returns the new rating, point change, and expected score.\n\n`/daily-puzzle`\nGet the daily chess puzzle\n\nReturns the single daily puzzle for today, or a past date via ?date=YYYY-MM-DD. Returns exactly one puzzle. The full puzzle database is not exposed.\n\nFull request and response schemas are in the [OpenAPI spec](https://www.chessigma.com/openapi.json).\n\nYou do not always need the API. These URLs drop a user straight into a live, client-side tool. Standardize on `fen` for positions and `pgn` for games. URL-encode the value.\n\n`/tools/analysis?fen=<FEN>`\nOpens the live analysis board on a position.\n\n`/tools/analysis?pgn=<PGN>`\nLoads a game for move-by-move replay and analysis.\n\n`/tools/next-move?fen=<FEN>`\nFinds the engine's best move for a position.\n\n`/tools/analysis/editor?fen=<FEN>`\nOpens the board editor on a position.\n\n`/games/<gameId>?move=<n>`\nJumps to a specific move in a submitted game.\n\nChessigma publishes a machine-readable discovery surface so AI agents can find and use it.\n\n`/openapi.json`: the OpenAPI 3.1 contract.`/.well-known/api-catalog`: RFC 9727 catalog.`/.well-known/agent-skills/index.json`: the agent skill index.", "url": "https://wpnews.pro/news/chessigma-api", "canonical_source": "https://www.chessigma.com/developers", "published_at": "2026-11-06 05:28:55+00:00", "updated_at": "2026-11-06 05:50:19.681300+00:00", "lang": "en", "topics": ["ai-agents", "agent-protocols", "developer-tools", "ai-tools"], "entities": ["Chessigma", "OpenAPI 3.1", "RFC 9727"], "also_reported_by": [], "alternates": {"html": "https://wpnews.pro/news/chessigma-api", "markdown": "https://wpnews.pro/news/chessigma-api.md", "text": "https://wpnews.pro/news/chessigma-api.txt", "jsonld": "https://wpnews.pro/news/chessigma-api.jsonld"}}