generated: '2026-08-16'
method: searched
source: https://uchecker.net/en/mcp
name: uChecker MCP Server
status: published
description: 'First-party hosted MCP server for uChecker email validation. Streamable HTTP transport,
  authenticated with the same uChecker API key used by the REST API (x-api-key header, or Authorization:
  Bearer <key>). Gives an agent single and bulk email validation, task polling, result paging, analytics
  and export without writing REST integration code.'
deployment:
  mode: remote
  endpoint: https://api.uchecker.net/mcp
  install: ''
  package: ''
  auth: api-key
  verified: probed
  probe_prior: (never probed)
  probe: gated
  probe_why: JSON-RPC error envelope -- the MCP server answered
  checked: '2026-09-11'
  source: claimed-backlog re-probe 2026-09-11
x-evidence:
  fetched: '2026-08-16'
  probe:
    url: https://api.uchecker.net/mcp
    method: POST
    body: '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'
    http_status: 401
    response: '{"jsonrpc":"2.0","error":{"code":-32001,"message":"Unauthorized: provide your UChecker
      API key in the x-api-key header or as Authorization: Bearer <key>."},"id":null}'
    verdict: The endpoint is live and speaks JSON-RPC — it returned a well-formed JSON-RPC error object,
      not an HTML page — but tools/list and initialize are both auth-gated behind a uChecker API key.
      Live inputSchema introspection therefore requires an authenticated session; the tool list below
      is transcribed verbatim from the provider's own MCP page (names + descriptions only) and the parameter
      shapes are crosswalked to the published OpenAPI operations in mcp/uchecker-tool-crosswalk.yml.
transport: streamable-http
authentication:
  type: api-key
  header: x-api-key
  alternate_header: 'Authorization: Bearer <key>'
  key_prefix: uk_
  obtain: https://app.uchecker.net
clients_documented:
- client: Claude Code (CLI)
  command: 'claude mcp add --transport http uchecker https://api.uchecker.net/mcp --header "x-api-key:
    uk_YOUR_KEY"'
- client: Cursor / VS Code / any MCP-compatible client
  config: "{\n  \"mcpServers\": {\n    \"uchecker\": {\n      \"type\": \"http\",\n      \"url\": \"https://api.uchecker.net/mcp\"\
    ,\n      \"headers\": { \"x-api-key\": \"uk_YOUR_KEY\" }\n    }\n  }\n}\n"
tool_count: 10
tools:
- name: validate_email
  description: Validate a single email address
- name: validate_emails
  description: Bulk-validate a list (up to 10,000 per call)
- name: wait_for_task
  description: Wait until a validation task completes
- name: get_task_status
  description: Task status and progress
- name: get_task_results
  description: Paged results with good/bad filtering
- name: get_task_analytics
  description: Deliverability and rejection reasons
- name: export_results
  description: Export results (CSV, good/bad lists)
- name: list_tasks
  description: Task history
- name: get_account_balance
  description: Credits balance
- name: get_account_stats
  description: Account-wide statistics
metering: Pricing matches the REST API — 1 email = 1 credit; syntactically invalid addresses are not charged.
  There is no separate MCP price list.
provider_guidance: uChecker's own MCP page notes that an SMTP check is a live conversation with the recipient's
  mail server and is subject to greylisting and receiver-side rate limits, so an agent should run validation
  as a background task rather than a synchronous step.