SerpKite MCP API

openapi: 3.2.0
info:
  title: SerpKite SERP MCP API
  version: 1.12.4
  description: 'Public search API (api.serpkite.com). Google results as clean JSON or Markdown

    for AI agents, plus a Google Custom Search–compatible endpoint. Official SDKs:

    `serpkite` on npm and PyPI, `github.com/serpkite/serpkite-go`. **Auth:** `Authorization: Bearer skt_live_…`. A bare `Authorization: skt_live_…`

    (no scheme) is also accepted, for MCP hosts that can''t add one. GET requests

    may pass `?api_key=` instead. `/customsearch/v1` also accepts Google''s `?key=`. **Bodies:** every vertical accepts `POST` with a JSON object or `GET` with the

    same parameters in the query string (only `GET /v1/search` is spelled out

    here). Unknown parameters are rejected with 400, and so is a parameter the

    endpoint would ignore (e.g. `time` on `/v1/scholar`, `ll` on `/v1/search`). To run many queries at once,

    use `POST /v1/batches`. **Formats:** `format=json` (default) returns the schemas below. `format=markdown` returns `text/markdown` for every vertical. `format=compact` and `fields=` return a reduced JSON object (same top-level

    keys, fewer item fields, `meta` always kept), so required item fields may be

    absent there. **Responses** share one envelope: `request` (the normalised request),

    `results` (the vertical''s primary list), vertical-specific extras and `meta`. All keys are snake_case. **Credits** are decimal numbers (e.g. `0.5`). Failed, empty and blocked

    responses are refunded. Every billed response carries `X-Credits-Used`,

    `X-Credits-Remaining`, `X-Cost-USD`, `X-Cache` (`HIT`|`MISS`), `X-Latency-Ms`,

    `X-Tokens-Estimate` and `X-Request-Id`. **Errors** share one body: `{"error":{"code","message","request_id"}}`. Upstream failures (`upstream_error`, `upstream_blocked`, `upstream_timeout`)

    are `503` with `Retry-After`, never billed and safe to retry. The API never

    returns `502` or `504`. `429` also carries `Retry-After`: `rate_limited` is

    the per-second limit; `daily_limit_reached` is the free daily limit of an

    account that never bought a pack, which resets at 00:00 UTC (the message

    names the limit and the billing page; buying any pack removes it). `403 account_restricted` means the account''s free use is paused because it

    appears to be one of several accounts run by the same person (same device

    or network, or requests in step with other accounts) or uses a disposable

    email address; buying any pack lifts it. **CORS:** `Access-Control-Allow-Origin: *` without credentials; the `X-*`

    headers above are exposed, so a browser playground can call the API with a key. The keyless `/playground/search` is the exception: it only answers serpkite.com

    and app.serpkite.com (other `Origin`s get 403). Credit table: search/news/images/videos/maps/places/shopping/scholar/patents/

    webpage/customsearch = 1 per page; place details = 1; `num=100` depth bundle = 7; reviews = 1 per 10;

    autocomplete = 0.5; `include_content` = +1 per fetched page;

    batches ×0.5 (from 2026-11-23 a batch depth request is 0.5 per page with

    results, without the bundle cap: `num=100` = 5); cache hit via `max_age` ×0.5. `engine=consensus` (search only) =

    the sum of one page per provider that returned results. **AI** (Claude writes, OpenAI''s Decisions API runs typed checks; a failed

    model step is never billed): an answer (`include_answer` on `/v1/search` and

    `/v1/news`, the model part of `/v1/answer`) = +2 over the result page, +4

    when it read pages (`include_content`, `/v1/answer` depth=standard);

    `/v1/extract` `summary` = +4 and `output_schema` = +4 per page;

    `/v1/research` = lite 30, standard 75, deep 200. Responses that used a

    model carry `meta.llm`. **AI assistants** (`/v1/chatgpt`, `/v1/gemini`, `/v1/copilot`,

    `/v1/ai_mode`, `/v1/brave_ai`): a `prompt` sent to the public assistant

    as a logged-out user; the response is its answer

    (`text`, `markdown`) with the `sources` it cited or listed,

    `search_queries`, `products` and `places` where the assistant shows them,

    and `mentions` for the brands and domains in `track`.'
servers:
- url: https://api.serpkite.com
- url: http://localhost:8080
security:
- bearer: []
tags:
- name: MCP
paths:
  /v1/mcp:
    post:
      summary: Remote MCP server (streamable HTTP, JSON-RPC 2.0).
      operationId: mcp
      description: 'Authenticates with an API key (`Authorization: Bearer skt_live_…`) or an

        OAuth 2.1 access token (`skt_oat_…`) issued by app-api.serpkite.com for

        this resource (MCP authorization spec). Without a valid credential the

        401 carries `WWW-Authenticate: Bearer resource_metadata="…/.well-known/oauth-protected-resource/v1/mcp", scope="mcp"`

        (plus `error="invalid_token"` when a credential was rejected). OAuth

        access tokens are only accepted here, not on the REST endpoints.'
      security:
      - bearer: []
      - oauth:
        - mcp
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              additionalProperties: true
      responses:
        '200':
          description: JSON-RPC response
          content:
            application/json:
              schema:
                type: object
                additionalProperties: true
        '202':
          description: Notification accepted
        '401':
          description: Missing, invalid, expired or revoked credential
          headers:
            WWW-Authenticate:
              description: RFC 9728 challenge pointing at the protected resource metadata
              schema:
                type: string
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
      tags:
      - MCP
components:
  schemas:
    Error:
      type: object
      required:
      - error
      properties:
        error:
          type: object
          required:
          - code
          - message
          properties:
            code:
              type: string
              description: '403: spend_cap_reached, key_limit_reached, account_restricted, forbidden. 409/422: idempotency_key_reused. 422: target_unavailable (the URL you asked for failed: its site answered 404, its domain doesn''t resolve; resending won''t help), no_pages. 429: rate_limited, daily_limit_reached. 503: upstream_error, upstream_blocked, upstream_timeout, unavailable (the API never sends 502 or 504)'
              examples:
              - unauthorized
              - invalid_request
              - insufficient_credits
              - rate_limited
              - daily_limit_reached
              - spend_cap_reached
              - key_limit_reached
              - account_restricted
              - idempotency_key_reused
              - forbidden
              - not_found
              - upstream_error
              - upstream_blocked
              - upstream_timeout
              - unavailable
              - internal
            message:
              type: string
            request_id:
              type: string
  securitySchemes:
    bearer:
      type: http
      scheme: bearer
    oauth:
      type: oauth2
      description: OAuth 2.1 for the remote MCP server only (authorization code + PKCE S256; app-api.serpkite.com is the authorization server).
      flows:
        authorizationCode:
          authorizationUrl: https://app-api.serpkite.com/oauth/authorize
          tokenUrl: https://app-api.serpkite.com/oauth/token
          refreshUrl: https://app-api.serpkite.com/oauth/token
          scopes:
            mcp: Use the SerpKite MCP tools, billed to your account
            offline_access: Stay connected with refresh tokens