Verify Claim

A Model Context Protocol (MCP) server that forces evidence-gated, honestly tiered claim reporting. Every claim an agent makes gets classified into an evidence tier (FACT / INFERENCE / SPECULATION / UNVERIFIED) with attached evidence — the antidote to the silent-unverified-claim failure mode ("pushed successfully", "the tests pass", "the API returned 200" — asserted without ever running the command).

Deterministic, no LLM, no network calls. Self-hostable, MCP-compatible with any agent (Claude Code, Cursor, Copilot, OpenClaw, Codex CLI).

Why it exists

The most common agent failure is not wrong reasoning — it's reporting a plausible-sounding result that was never verified. mcp-verify-claim installs a hard gate: no unverified claim can be reported as fact.

The pattern it fits (agent tooling that answers with evidence, not opinion)

When you give an agent access to real operations (edits, checks, rule evaluation, mutations) through MCP, the value is that it can answer with evidence instead of opinion — it ran the check, it saw the real state, it can prove what it did. But that only holds if the agent is forced to attach the evidence. A rules-and-checks surface ("is the module valid?", "did this state change slice apply?", "what actually changed?") is exactly the high-value case: each check produces a machine-verifiable result.

mcp-verify-claim is the gate that guarantees the agent reports the result with its evidence attached (exit code, real read-back, actual HTTP status) and cannot pass off a guess or an unrun step as truth. Pair it with any MCP surface that exposes operations, and the agent's answers become auditable, line-by-line, instead of plausible.

Tools

• tier_claim(claim, evidence, verification_kind) — classify a claim into a tier + verdict (TRUST / REVIEW / DO-NOT-REPORT) + honest next-action.
• check_claim(claim) — deterministic scan for fabrication/hedging signals (completion-without-artifact, "the API returned", hedge words).
• report_templates() — the canonical STATUS / EVIDENCE / GAPS completion shape and the 6-step behavioral loop.
• tier_definitions() — the FACT / INFERENCE / SPECULATION / UNVERIFIED definitions.

Evidence tier (the core)

Tier	Meaning	Verdict
FACT	Saw it in raw tool output (exit code, body, file read-back, HTTP status)	TRUST
INFERENCE	Deduced from facts; show the chain	REVIEW
SPECULATION	A guess; never report as truth	REVIEW
UNVERIFIED	No evidence produced	DO-NOT-REPORT

Install & run

One command (recommended) — installs from the repo, no PyPI token needed:

uv tool install git+https://github.com/sudo-ai-git/mcp-verify-claim
mcp-verify-claim                         # run stdio server
mcp-verify-claim --http --port 8137      # or Streamable HTTP for remote use

Or with pipx: pipx install git+https://github.com/sudo-ai-git/mcp-verify-claim

Direct from source (fallback):

pip install mcp
python3 mcp_server.py

Claude Desktop / agent config

{ "mcpServers": {
    "verify-claim": { "command": "mcp-verify-claim", "args": [] }
}}

Example

tier_claim("Successfully deployed", evidence="", verification_kind="")
--> tier UNVERIFIED, verdict DO-NOT-REPORT
    signals: [high] completion claim without artifact
    next: go get the evidence before reporting

tier_claim("Deploy is live", evidence="origin/main SHA==local HEAD, HTTP 200", verification_kind="read_back")
--> tier FACT, verdict TRUST

Part of a family

This is one of three deterministic, no-LLM agent-trust MCP servers by sudo-ai-git:

• mcp-skill-sec — pre-install skill/security audit
• mcp-verify-claim — evidence-gated, honestly-tiered claim reporting (this repo)
• mcp-benchmark-hygiene — pytest config-leakage / eval-honesty detection

Sibling product: mcp-token-saver — token-cost proxy + analyzer for agent conversations (dedupes redundant tokens before they're billed; live-proven 74% cut). Discussion

Also in the family (a free CLI, not an MCP server): harness-audit — deterministic agent-eval / benchmark-grading hygiene audit that catches the same silent config-leakage mis-scoring class. Free lead-magnet; the same verification discipline, zero dependencies, auditable line-by-line.

License & provenance

MIT. Written by sudo-ai-git. Standalone behavioral-rigor tool; encodes no proprietary method. MCP expression of the verify-before-claim agent skill.

Official MCP Registry metadata

mcp-name: io.github.sudo-ai-git/mcp-verify-claim

Hire a custom integration

Need this connected to your internal system (auth, logging, security-scan pass, hosted)? Open a custom-build request. MIT reference assets are free to use either way.