Lichess Analysis API

openapi: 3.1.0
info:
  version: 2.0.144
  title: Lichess.org API reference Account Analysis API
  contact:
    name: Lichess.org API
    url: https://lichess.org/api
    email: contact@lichess.org
  x-logo:
    url: https://lichess1.org/assets/logo/lichess-pad12.svg
  license:
    name: AGPL-3.0-or-later
    url: https://www.gnu.org/licenses/agpl-3.0.txt
  description: '# Introduction

    Welcome to the reference for the Lichess API! Lichess is free/libre,

    open-source chess server powered by volunteers and donations.

    - Get help in the [Lichess Discord channel](https://discord.gg/lichess)

    - API demo app with OAuth2 login and gameplay: [source](https://github.com/lichess-org/api-demo) / [demo](https://lichess-org.github.io/api-demo/)

    - API UI app with OAuth2 login and endpoint forms: [source](https://github.com/lichess-org/api-ui) / [website](https://lichess.org/api/ui)

    - [Contribute to this documentation on Github](https://github.com/lichess-org/api)

    - Check out [Lichess widgets to embed in your website](https://lichess.org/developers)

    - [Download all Lichess rated games](https://database.lichess.org/)

    - [Download all Lichess puzzles with themes, ratings and votes](https://database.lichess.org/#puzzles)

    - [Download all evaluated positions](https://database.lichess.org/#evals)


    ## Endpoint

    All requests go to `https://lichess.org` (unless otherwise specified).


    ## Clients

    - [Python general API](https://github.com/lichess-org/berserk)

    - [MicroPython general API](https://github.com/mkomon/uberserk)

    - [Python general API - async](https://pypi.org/project/async-lichess-sdk)

    - [Python Lichess Bot](https://github.com/lichess-bot-devs/lichess-bot)

    - [Python Board API for Certabo](https://github.com/haklein/certabo-lichess)

    - [Java general API](https://github.com/tors42/chariot)

    - [JavaScript & TypeScript general API](https://github.com/devjiwonchoi/equine)

    - [LichessNET - C# API Wrapper](https://github.com/Rabergsel/LichessNET)

    - [.NET general API](https://github.com/Dblike/LichessSharp)


    ## Rate limiting

    All requests are rate limited using various strategies,

    to ensure the API remains responsive for everyone.

    Only make one request at a time.

    If you receive an HTTP response with a [429 status](https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#429),

    you have exceded one of the rate limits.

    In most cases, waiting one minute before retrying will be sufficient, but some limits may require longer.

    Reduce your request frequency before retrying.


    ## Streaming with ND-JSON

    Some API endpoints stream their responses as [Newline Delimited JSON a.k.a. **nd-json**](https://github.com/ndjson/ndjson-spec), with one JSON object per line.


    Here''s a [JavaScript utility function](https://gist.github.com/ornicar/a097406810939cf7be1df8ea30e94f3e) to help reading NDJSON streamed responses.


    ## Authentication

    ### Which authentication method is right for me?

    [Read about the Lichess API authentication methods and code examples](https://github.com/lichess-org/api/blob/master/example/README.md)


    ### Personal Access Token

    Personal API access tokens allow you to quickly interact with Lichess API without going through an OAuth flow.

    - [Generate a personal access token](https://lichess.org/account/oauth/token)

    - `curl https://lichess.org/api/account -H "Authorization: Bearer {token}"`

    - [NodeJS example](https://github.com/lichess-org/api/tree/master/example/oauth-personal-token)


    ### Token Security

    - Keep your tokens secret. Do not share them in public repositories or public forums.

    - Your tokens can be used to make your account perform arbitrary actions (within the limits of the tokens'' scope). You remain responsible for all activities on your account.

    - Do not hardcode tokens in your application''s code. Use environment variables or a secure storage and ensure they are not shipped/exposed to users. Be especially careful that they are not included in frontend bundles or apps that are shipped to users.

    - If you suspect a token has been compromised, revoke it immediately.


    To see your active tokens or revoke them, see [your Personal API access tokens](https://lichess.org/account/oauth/token).


    ### Authorization Code Flow with PKCE

    The authorization code flow with PKCE allows your users to **login with Lichess**.

    Lichess supports unregistered and public clients (no client authentication, choose any unique client id).

    The only accepted code challenge method is `S256`.

    Access tokens are long-lived (expect one year), unless they are revoked.

    Refresh tokens are not supported.


    See the [documentation for the OAuth endpoints](#tag/OAuth) or

    the [PKCE RFC](https://datatracker.ietf.org/doc/html/rfc7636#section-4) for a precise protocol description.


    - [Demo app](https://lichess-org.github.io/api-demo/)

    - [Minimal client-side example](https://github.com/lichess-org/api/tree/master/example/oauth-app)

    - [Flask/Python example](https://github.com/lakinwecker/lichess-oauth-flask)

    - [Java example](https://github.com/tors42/lichess-oauth-pkce-app)

    - [NodeJS Passport strategy to login with Lichess OAuth2](https://www.npmjs.com/package/passport-lichess)


    #### Real life examples

    - [PyChess](https://github.com/gbtami/pychess-variants) ([source code](https://github.com/gbtami/pychess-variants))

    - [Lichess4545](https://www.lichess4545.com/) ([source code](https://github.com/cyanfish/heltour))

    - [English Chess Federation](https://ecf.octoknight.com/)

    - [Rotherham Online Chess](https://rotherhamonlinechess.azurewebsites.net/tournaments)


    ### Token format

    Access tokens and authorization codes match `^[A-Za-z0-9_]+$`.

    The length of tokens can be increased without notice. Make sure your application can handle at least 512 characters.

    By convention tokens have a recognizable prefix, but do not rely on this.

    '
servers:
- url: https://lichess.org
- url: https://lichess.dev
- url: http://localhost:{port}
  variables:
    port:
      default: '8080'
- url: http://l.org
tags:
- name: Analysis
  description: 'Access Lichess cloud evaluations database.

    <https://lichess.org/analysis>

    '
paths:
  /api/cloud-eval:
    get:
      operationId: apiCloudEval
      summary: Get cloud evaluation of a position.
      description: 'Get the cached evaluation of a position, if available.

        Opening positions have more chances of being available. There are about 320 million positions in the database.

        Up to 5 variations may be available. Variants are supported.

        Use this endpoint to fetch a few positions here and there.

        If you want to download a lot of positions, [get the full list](https://database.lichess.org/#evals) from our exported database.

        '
      tags:
      - Analysis
      security: []
      parameters:
      - in: query
        name: fen
        required: true
        description: X-FEN of the position
        schema:
          type: string
        example: r1bqkbnr/pppp1ppp/2n5/1B2p3/4P3/5N2/PPPP1PPP/RNBQK2R b KQkq - 3 3
      - in: query
        name: multiPv
        description: Number of variations
        schema:
          type: integer
          default: 1
      - in: query
        name: variant
        description: Variant
        schema:
          $ref: '#/components/schemas/VariantKey'
      responses:
        '200':
          description: The evaluation of the position.
          headers:
            Access-Control-Allow-Origin:
              schema:
                type: string
                default: '''*'''
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/CloudEval'
        '404':
          description: The position was not found in the cloud evaluation database.
          content:
            application/json:
              schema:
                properties:
                  error:
                    type: string
                    example: No cloud evaluation available for that position
components:
  schemas:
    CloudEval:
      type: object
      required:
      - depth
      - fen
      - knodes
      - pvs
      properties:
        depth:
          type: integer
        fen:
          type: string
        knodes:
          type: integer
        pvs:
          type: array
          items:
            oneOf:
            - type: object
              title: Non-mate variation
              required:
              - cp
              - moves
              properties:
                cp:
                  type: integer
                  description: Evaluation in centi-pawns, from White's point of view
                moves:
                  type: string
                  description: 'Variation in UCI notation (King to rook for Chess960-compatible

                    castling notation)

                    '
            - type: object
              title: Mate variation
              required:
              - mate
              - moves
              properties:
                mate:
                  type: integer
                  description: Evaluation in moves to mate, from White's point of view
                moves:
                  type: string
                  description: 'Variation in UCI notation (King to rook for Chess960-compatible

                    castling notation)

                    '
      example:
        fen: r1bqkbnr/pppp1ppp/2n5/1B2p3/4P3/5N2/PPPP1PPP/RNBQK2R
        knodes: 106325
        depth: 29
        pvs:
        - moves: d1e2 d8e7 a2a4 a7a6 b5c4 d7d6 d2d3 g8f6 c1e3 c6a5
          cp: 41
        - moves: c2c3 a7a6 b5a4 g8f6 d2d3 b7b5 a4b3 h7h6 a2a4 c8b7
          cp: 39
        - moves: d2d3 d8f6 c2c3 a7a6 b5a4 f8c5 d3d4 c5a7 c1e3 g8e7
          cp: 37
    VariantKey:
      type: string
      enum:
      - standard
      - chess960
      - crazyhouse
      - antichess
      - atomic
      - horde
      - kingOfTheHill
      - racingKings
      - threeCheck
      - fromPosition
      example: standard
      default: standard
  securitySchemes:
    OAuth2:
      type: oauth2
      description: 'Read [the introduction for how to make authenticated requests](#description/authentication).

        '
      flows:
        authorizationCode:
          authorizationUrl: https://lichess.org/oauth
          tokenUrl: https://lichess.org/api/token
          scopes:
            preference:read: Read your preferences
            preference:write: Write your preferences
            email:read: Read your email address
            engine:read: Read your external engines
            engine:write: Create, update, delete your external engines
            challenge:read: Read incoming challenges
            challenge:write: Create, accept, decline challenges
            challenge:bulk: Create, delete, query bulk pairings
            study:read: Read private studies and broadcasts
            study:write: Create, update, delete studies and broadcasts
            tournament:write: Create tournaments
            racer:write: Create and join puzzle races
            puzzle:read: Read puzzle activity
            puzzle:write: Write puzzle activity
            team:read: Read private team information
            team:write: Join, leave teams
            team:lead: Manage teams (kick members, send PMs)
            follow:read: Read followed players
            follow:write: Follow and unfollow other players
            msg:write: Send private messages to other players
            board:play: Play with the Board API
            bot:play: Play with the Bot API. Only for [Bot accounts](#tag/bot/POST/api/bot/account/upgrade)
            web:mod: Use moderator tools (within the bounds of your permissions)