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Misc

Custom API (OpenAPI) connector

The Custom API connector turns any REST API described by an OpenAPI 3.x document into MCP tools. You paste the spec (JSON or YAML) plus a base URL and auth; OrgMCP compiles each operation into a namespaced tool at save time. It is tools-only — there is no knowledge-source picker or RAG crawler. An LLM agent calls the API live; only the actual call reaches the network.

Connect

  1. In the admin console, open Connectors → Add → Custom API (OpenAPI).
  2. Paste the Base URL (e.g. https://api.example.com). Every operation path is resolved against it. The host must be publicly routable.
  3. Paste the full OpenAPI 3.x spec (JSON or YAML). Local $refs into #/components/… are resolved; remote/URL $refs are not followed.
  4. Choose an auth scheme: none, bearer, header (with a header name such as X-Api-Key), basic (username + password), or query (with a query-param name). Supply the token where applicable.
  5. Click Test connection, then Add.

Choosing which operations become tools

  • By default only read operations (GET / HEAD) are exposed. Set Expose write operations to true to also expose POST / PUT / PATCH / DELETE.
  • Use the Operation allowlist to narrow the surface: a comma-separated list of operationIds, METHOD /path entries, or OpenAPI tag names. Leave it blank to expose everything up to the tool cap.
  • At most 40 operations are compiled into tools (a context-budget guard); the rest are dropped and the UI notes the truncation.

Tool naming

Tools are namespaced capi_<slug>__<operationId>, where <slug> derives from the connector display name. Two connectors with the same name get deduped slugs so tools never collide.

Network & safety

  • The base URL and every resolved DNS record must be publicly routable. Private, loopback, CGNAT, and cloud-metadata addresses are refused (SSRF protection).
  • Responses larger than ~60,000 characters are truncated before they reach the model, with a truncated flag on the result.
  • The pasted spec is compiled on save and then discarded — only the compiled operation list plus your endpoint and auth are stored (encrypted per tenant).

Availability: Team plan and higher. See also Remote MCP server for proxying another MCP endpoint, or PostgreSQL for a live read-only SQL connector.