mcp-verify-claim

mcp-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.

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

pip install mcp
# Claude Desktop / agent config:
# { "mcpServers": { "verify-claim": { "command": "python3",
#       "args": ["/absolute/path/to/mcp_server.py"] } } }
python3 mcp_server.py

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

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