generated: '2026-08-31'
method: searched
source: https://reefapi.com/docs (Authentication section) + https://reefapi.com/mcp + openapi/reefapi-openapi.json + live 401 probe 2026-08-31
docs: https://reefapi.com/docs
name: ReefAPI
slug: reefapi
summary:
  model: single-credential, no OAuth, no scopes
  types:
  - apiKey
  - http-bearer
  api_key_in:
  - header
  oauth2: false
  openid_connect: false
  mtls: false
  note: >-
    One key covers the entire 183-engine catalog and the MCP server — there is no
    per-engine credential, no scope surface and no token exchange. The same key is
    presented two different ways depending on the surface, which is the one thing an
    integrator has to get right.
schemes:
- name: ApiKeyAuth
  type: apiKey
  in: header
  parameter: x-api-key
  surface: REST
  applies_to: all 1528 operations (declared as a global `security` requirement in the OpenAPI)
  sources:
  - openapi/reefapi-openapi.json
  - https://reefapi.com/docs
- name: BearerKey
  type: http
  scheme: bearer
  header: Authorization
  surface: MCP (https://api.reefapi.com/mcp)
  applies_to: the call_engine tool only
  sources:
  - https://reefapi.com/mcp
  - https://reefapi.com/llms.txt
  note: >-
    The MCP server takes the SAME ReefAPI key but as 'Authorization: Bearer <key>',
    not as x-api-key. Not declared in the OpenAPI (the MCP endpoint is outside the spec).
key_management:
  issued_from: https://reefapi.com/signup (dashboard)
  prefix: ak_live_
  display_policy: full key shown once at creation
  rotation_documented: false
  guidance: "Keep it server-side; never ship it to a browser. (docs, Authentication section)"
anonymous_access:
  rest: false
  mcp_discovery: true
  detail: >-
    PROBED 2026-08-31. The MCP methods initialize, tools/list, prompts/list and
    resources/list all return 200 with no Authorization header. Four of the five tools
    (search_engines, get_catalog, get_engine_schema, get_action_schema) are documented
    and verified keyless. Only call_engine authenticates and spends credits. The
    OpenAPI itself (https://api.reefapi.com/openapi.json) and the RFC 9727 api-catalog
    are also anonymous.
failure_behavior:
  status: 401
  code: AUTH_FAILED
  envelope: '{"ok":false,"meta":{...},"error":{"code":"AUTH_FAILED","message":"auth: no_key","retryable":false}}'
  observed: '2026-08-31 POST https://api.reefapi.com/currency/v1/convert with no key'
  note: The 401 body is the standard success envelope with ok=false — error semantics are uniform with the happy path.
gaps:
- "No /.well-known/openid-configuration, /.well-known/oauth-authorization-server or /.well-known/oauth-protected-resource on either host (all 404) — the MCP server is key-auth, not OAuth-protected, so RFC 9728 protected-resource metadata does not apply."
- "No documented key-rotation or key-expiry policy."
- "No IP allow-listing, per-key scope restriction or read-only key variant is documented."