Claim Grounding

npx add-mcp 'https://claim-grounding.prospectintel.workers.dev/mcp'

TruePoint Claim Grounding

Pay-per-call claim checks for AI agents. Sources: Wikipedia, Wikidata, Google News, Europe PMC (PubMed), FRED and SEC EDGAR. USDC on Base via x402. No API key.

https://claim-grounding.prospectintel.workers.dev

• POST /v1/extract_claims — $0.05 - split any AI answer into checkable claims; each checkable claim gets a ready-to-send next_step
• POST /v1/quick_check — $0.15 — fast supported / contradicted / unsure verdict on one claim with 1-2 sources
• POST /v1/verify_claim — $1.00
• POST /v1/check_answer — $1.00
• POST /v1/deep_verify — $0.75 — Wikipedia, Google News titles, Europe PMC (reviews, meta-analyses and trials, for health and science claims), FRED (latest official US economic data: inflation, unemployment, fed funds, GDP growth, Treasury and mortgage rates), Wikidata (structured facts: dates, quantities, positions held, predecessors) and SEC EDGAR (US public-company filings: revenue / net income, deregistration and delisting, former names). Flags contradiction when sources disagree. Async: returns job_id. Each citation carries source_type: wikipedia, news, europepmc, fred, wikidata or sec_edgar.
• POST /v1/deep_research/lite — $5.00 — Deep Research Lite. Requires confirmed: true.
• POST /v1/deep_research — $8.00 — Deep Research Core. Requires confirmed: true.
• POST /v1/deep_research/pro — $15.00 — Deep Research Pro. Requires confirmed: true.
• GET /v1/jobs/{id} — free — poll async results.

Deep Research never auto-spends: without confirmed: true the call returns 400 and nothing is charged.

Your own sources (1.4.6)

verify_claim, check_answer and deep_verify accept an optional sources array (up to 10). Each item is {"url":"https://..."} (a public https page we fetch: 3.5 s timeout, 512 KB cap, text/HTML/JSON only) or {"text":"...","title":"...","url":"..."} (up to 20,000 characters, no fetch). Your sources are used next to the public ones and cited with source_type: "caller"; sources_used in the response reports each one (used, fetch_failed or empty). Add "sources_only": true to judge only against your sources. Non-https URLs (http, file,...), private, loopback, link-local and cloud-metadata addresses, IP-literal hosts, custom ports and URLs with credentials are rejected with HTTP 400 before payment, so nothing is charged. Checks that use your sources are never cached or shared with other callers.

POST /v1/verify_claim {"claim":{"text":"Acme's 2025 revenue was $12 million"},"sources":[{"title":"Acme 2025 annual report","text":"Acme reported 2025 revenue of $12 million."}],"sources_only":true}

MCP

Public remote MCP server (Streamable HTTP, JSON-RPC over POST): https://claim-grounding.prospectintel.workers.dev/mcp. Server card: /.well-known/mcp/server-card.json. tools/call does not charge; it returns x402 payment instructions for the paid HTTP route that runs the work.

Accuracy results and limits: /accuracy.

Verdicts

Every checked claim gets verdict, one of:

• supported — a cited source entails the claim.
• contradicted — a cited source shows the claim is false (and was not true in the relevant sense).
• outdated — the claim was true at some point but a cited source shows it no longer is (renamed, reclassified, left, merged, guidance reversed).
• mixed — credible evidence points in different directions (deep_verify also sets contradiction: true).
• insufficient_evidence — not enough reliable evidence to decide; the service abstains (forecasts, vague or unverifiable claims, association offered as causation).

Since 1.2.0 each result also carries status_detail (why, e.g. status_changed, predictive_claim, sources_disagree) and legacy_verdict with the pre-1.2.0 value (supported, contradicted, not_found, conflict): outdated maps to contradicted, mixed to conflict, insufficient_evidence to not_found. Prices are unchanged.

Examples

POST /v1/extract_claims {"text":"Paris is the capital of France. The Eiffel Tower opened in 1889."}
POST /v1/verify_claim   {"claim":{"text":"Paris is the capital of France"}}
POST /v1/check_answer   {"answer":"Paris is the capital of France."}
POST /v1/deep_verify    {"claim":{"text":"Paris is the capital of France"}}
POST /v1/deep_research  {"confirmed":true,"answer":"Acme Corp was founded in 1999."}

Version 1.5.0. Pay to 0x485FfC037f02dDDc154A454a9cA89C4B1b29e25b on Base, USDC, x402 v2, Coinbase CDP facilitator. Discovery: /.well-known/x402 · /openapi.json · /llms.txt

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