generated: '2026-08-13'
method: derived
source: >-
  mcp/sendgrid-mcp-tools-list.json (live tools/list from https://mcp.twilio.com/docs,
  probed 2026-08-13) bound against the 63 refined OpenAPI documents in openapi/
  (389 operations, every one carrying an operationId).
description: >-
  Crosswalk between the tools Twilio's hosted MCP server actually exposes for
  SendGrid and the SendGrid v3 REST operations in this repo. THE HEADLINE
  FINDING IS THE SHAPE OF THE MISMATCH: the hosted server is a DOCUMENTATION
  server, not an execution server. Its two tools search and retrieve API
  specifications; NEITHER is backed by a SendGrid REST operation, and NONE of
  the 389 SendGrid operations has a corresponding MCP tool. An agent can use
  this server to discover how to call SendGrid, then must call the REST API
  directly with a bearer API key. Recording that honestly matters more than
  manufacturing name-matched rows: a crosswalk claiming coverage here would
  assert an agent can send mail through MCP, which it cannot.
surfaces:
  openapi:
    path: openapi/
    documents: 63
    operations: 389
    base_url: https://api.sendgrid.com
    eu_base_url: https://api.eu.sendgrid.com
    auth: bearer API key (Authorization header)
    gated: false
  mcp:
    url: https://mcp.twilio.com/docs
    transport: streamable-http (JSON-RPC over HTTPS POST)
    auth: none
    gated: false
    note: >-
      Live and anonymous — tools/list returned full inputSchemas without
      credentials, so the schemas below are the REAL ones, not inferred.
    server: {name: twilio-docs-mcp, version: 0.1.0, protocolVersion: '2025-11-25'}
  graphql:
    endpoint: null
    note: >-
      SendGrid publishes no GraphQL API. graphql/sendgrid-schema.graphql in this
      repo is a pipeline-generated projection of the REST surface, not a
      provider-served endpoint, so it is not crosswalked here.
  skills:
    path: skills/
    count: 8
    note: >-
      Twilio's published SendGrid Agent Skills are the layer that actually binds
      an agent to REST operations (see skills/_index.yml). They reference
      operations directly, not MCP tools.
crosswalk: []
crosswalk_note: >-
  Empty by measurement, not by omission. Every tool the server exposes is
  documentation-scoped; no tool wraps a SendGrid REST operation, so there is no
  tool-to-operationId binding to record.
mcp_only:
  - tool: twilio__search
    category: discovery
    reason: >-
      Natural-language search over Twilio/SendGrid documentation and API
      operations. Backed by Twilio's docs index, not by any public SendGrid REST
      endpoint. Accepts product="sendgrid" to scope results to the SendGrid
      surface; returns ids of the form op::{spec}::{operationId} that match the
      tsg_* spec identifiers in openapi/_original/.
    confidence: high
  - tool: twilio__retrieve
    category: discovery
    reason: >-
      Returns the full parameter/response schema for an operation id produced by
      twilio__search. This is spec retrieval — the same content as the OpenAPI in
      openapi/ — not an API call against a SendGrid account.
    confidence: high
rest_only:
  count: 389
  note: >-
    All 389 SendGrid v3 operations are rest_only: there is no MCP tool that
    invokes any of them. Rather than enumerate every operationId here, the
    authoritative list is the 63 documents in openapi/ (each operation carries an
    operationId) and the tool-shaped subset an execution server would expose is
    kept as the DERIVED candidate list in mcp/sendgrid-mcp.yml.
  representative:
    - {operationId: SendMail, method: POST, path: /v3/mail/send, spec: openapi/sendgrid-mail-send-api-openapi.yml}
    - {operationId: GetMailBatch, method: GET, path: '/v3/mail/batch/{batch_id}', spec: openapi/sendgrid-mail-batch-api-openapi.yml}
    - {operationId: ListContact, method: GET, path: /v3/marketing/contacts, spec: openapi/sendgrid-contacts-api-openapi.yml}
    - {operationId: SearchContact, method: POST, path: /v3/marketing/contacts/search, spec: openapi/sendgrid-contacts-api-openapi.yml}
    - {operationId: CreateSingleSend, method: POST, path: /v3/marketing/singlesends, spec: openapi/sendgrid-single-sends-api-openapi.yml}
    - {operationId: ListStat, method: GET, path: /v3/subusers/stats, spec: openapi/sendgrid-subuser-statistics-api-openapi.yml}
coverage:
  mcp_tools: 2
  mcp_tools_bound_to_rest: 0
  rest_operations: 389
  rest_operations_with_tool: 0
  rest_coverage_pct: 0.0
  tool_coverage_pct: 0.0
  interpretation: >-
    0% execution coverage, 100% discovery coverage. Twilio ships an agent surface
    that tells an agent exactly how to call SendGrid and ships nothing that calls
    it. The gap is closed today by the SendGrid Agent Skills in skills/ plus a
    direct bearer-key REST call.
x-evidence:
  fetched: '2026-08-13'
  tools_list: mcp/sendgrid-mcp-tools-list.json
  http_status: 200