Lichess External engine API
**This API is in alpha and subject to change.**Use or provide external engine analysis.External engines can provide analysis on pages like the[analysis board](https://lichess.org/analysis), running as a serviceoutside of the browser, or even on a different machine.
Lichess External engine API is one of 23 APIs that Lichess publishes on the APIs.io network, described by a machine-readable OpenAPI specification and an AsyncAPI event-driven specification.
This API exposes 2 JSON Schema definitions.
Tagged areas include External engine. The published artifact set on APIs.io includes an OpenAPI specification, API documentation, an AsyncAPI specification, a JSON-LD context, and 2 JSON Schemas.
This API exposes 8 operations across 5 paths, and defines 6 schemas. It is described by OpenAPI 3.1.0, at version 2.0.144.
Requests are made against 4 base URLs: https://lichess.org, https://lichess.dev, http://localhost:{port}, http://l.org.
Metadata
The identity and technical contract details declared by the specification.
Authentication & Security 1
Lichess External engine API declares
1 security scheme
for authenticating requests.
It supports OAuth 2.0 (OAuth2) using the authorizationCode flow, exposing 23 scopes.
OAuth2— Read [the introduction for how to make authenticated requests](description/authentication).
Paths & Operations 8
Across 5 paths, the API surfaces 8 operations — 1 DELETE, 2 GET, 4 POST, 1 PUT. Each is listed below with its method, path, parameters, and response codes.
This API is in alpha and subject to change. Use or provide external engine analysis. External engines can provide analysis on pages like the [analysis board](https://lichess.org/a…
Schemas 6
The contract defines 6 schemas that model the data the API accepts and returns. The most detailed are ExternalEngine (8 properties), ExternalEngineWorkCommon (7 properties), ExternalEngineRegistration (6 properties), Ok (1 property). Each schema is shown below with its type and property counts.
Specification
The full machine-readable OpenAPI contract behind this narrative.
Source
More from Lichess 12
Other APIs Lichess publishes across the network.
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