generated: '2026-08-13'
method: searched
status: published
source: https://developers.smtp2go.com/docs/mcp
deployment:
  mode: remote
  endpoint: https://developers.smtp2go.com/mcp
  install: null
  package: null
  auth: api-key
  verified: probed
  note: Verified by POSTing initialize and tools/list to the endpoint anonymously on 2026-08-13; both
    returned HTTP 200 over text/event-stream. Discovery tools answer without credentials. execute-request
    requires an SMTP2GO API key in the X-Smtp2go-Api-Key request header — the same key the REST API uses,
    not OAuth. Claude Desktop is documented as connecting through the npx mcp-remote bridge, but that
    is a client-side shim for header support, not a provider-published stdio package, so the mode is remote,
    not both.
  probe_prior: (never probed)
  probe: live
  probe_why: live
  checked: '2026-09-11'
  source: claimed-backlog re-probe 2026-09-11
server:
  name: SMTP2GO-API-Docs
  version: 3.0.4
  transport: streamable-http
  url: https://developers.smtp2go.com/mcp
  protocol_version: '2025-06-18'
  capabilities:
    tools:
      listChanged: false
  authentication:
    scheme: apiKey
    in: header
    name: X-Smtp2go-Api-Key
    obtain: https://app.smtp2go.com/sending/apikeys/
    recommended_permissions:
    - /email/send
    - /allowed_senders/view
    - /domain/view
documented_clients:
- client: Codex App / Codex CLI
  transport: streamable-http
  native: true
- client: Claude Code
  transport: streamable-http
  native: true
- client: Gemini CLI
  transport: streamable-http
  native: true
- client: Cursor
  transport: streamable-http
  native: true
- client: Claude Desktop
  transport: stdio-bridge
  native: false
  via: npx -y mcp-remote@latest
- client: Lovable
  transport: streamable-http
  native: true
tools:
- name: list-endpoints
  description: Lists all API paths and their HTTP methods with summaries, organized by path. Results can
    be passed directly into 'get-endpoint'.
  input_schema_properties: []
- name: get-endpoint
  description: Gets detailed information about a specific API endpoint, including security schemes and
    servers.
  input_schema_properties:
  - path
  - method
- name: search-endpoints
  description: Performs a deep search through paths, operations, and parameters to discover relevant API
    endpoints.
  input_schema_properties:
  - pattern
- name: execute-request
  description: Executes an API request with a given HAR request object.
  input_schema_properties:
  - harRequest
- name: get-server-variables
  description: Gets the server variables for each server within a specific OpenAPI spec.
  input_schema_properties: []
tools_list_file: smtp2go-mcp-tools-list.json
x-evidence:
  fetched: '2026-08-13'
  initialize:
    url: https://developers.smtp2go.com/mcp
    http_status: 200
    content_type: text/event-stream
    server_info:
      name: SMTP2GO-API-Docs
      version: 3.0.4
  tools_list:
    url: https://developers.smtp2go.com/mcp
    http_status: 200
    tool_count: 5
    authenticated: false
note: 'This is a documentation/gateway-shaped MCP server, not one tool per API capability: five generic
  tools sit in front of the whole 73-operation v3 REST surface, and the agent reaches a specific capability
  by discovering it with search-endpoints/get-endpoint and then calling execute-request with a HAR request
  object. get-endpoint returns the provider''s authoritative OpenAPI 3.1.0 fragment for each path, which
  is how openapi/_original/smtp2go-openapi-original.yml was harvested. See mcp/smtp2go-tool-crosswalk.yml
  for the tool-to-operation binding.'