MCP Verification Gate: check an MCP server or an A2A agent before you connect or delegate

Last 30 days

Uptime

100%

Response time

123 ms typical, 123 ms slowest 5%

Last check

8 h ago

Next check

any minute now

How to call it

Add it to any MCP client that supports remote servers.

{
  "mcpServers": {
    "mcp-verification-gate-check-an-mcp-server-or-an-a2a-agent-be": {
      "type": "http",
      "url": "https://gate.horizonshield.dev/mcp"
    }
  }
}

6 tools

• get_conditions

  Return the five conditions this gate measures, what it explicitly does not verify, and the tier definitions. Takes no arguments and returns identical output every time. Read this before running a check so you know what a verdict does and does not claim.

• check_conformance

  Measure a public MCP endpoint against five conditions: it speaks MCP, it publishes an A2A agent card, it declares who pays it, identical input returns identical output, and the verdict itself can be recomputed by anyone. Free, no key. Conformance and disclosure only; this says no

• verify_verdict

  Take a verdict this gate issued and recompute its record_sha256 independently. Removes record_sha256 and recompute_note, serialises the remainder in key order, and hashes it. Returns whether the verdict was altered after it was issued. You do not have to trust the party that issu

• lookup_server

  Returns one record (not a list). Look up what this register already holds about an MCP endpoint: whether it is watched, how often it is re-measured, how many measurements exist, when the first and latest were taken, and the latest verdict with the record_sha256 you can recompute

• is_verified

  A single machine-first answer for an agent deciding whether to trust an MCP endpoint BEFORE it connects. Returns verified (true only when the latest scheduled measurement passed every measured condition; null otherwise, never false), a state enum saying which case it is, measured

• preflight_agent

  Call this before handing work to an A2A agent you have not used before. Fetches the agent's public card (https://<agent>/.well-known/agent-card.json, one request), reports whether it declares the A2A Conduct Extension, who it says pays it (the compensation declaration, as declare

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