Claim Grounding

TruePoint Prospect Intelligence & Claim Grounding

Pay-per-call APIs for AI agents. Pay USDC on Base per call with x402. No API key, no signup. People can pay by card instead.

• Prospect Intelligence: work-email lookup and company research for sales agents.
• Claim Grounding: checks factual claims against public sources and returns a verdict, confidence and citations.

Accuracy results: https://claim-grounding.prospectintel.workers.dev/accuracy (92 of 100 hard claims right on Deep verify, 0 confidently wrong; 38 of 38 found emails exactly right). Read the limitations there too.

30-second quickstart

Option A: Coinbase agentic wallet (awal)

npx awal@latest status          # sign in / check wallet
npx awal@latest balance         # needs USDC on Base
npx awal@latest x402 pay https://claim-grounding.prospectintel.workers.dev/v1/verify_claim \
  -X POST -d '{"claim":{"text":"The Eiffel Tower is in Paris"}}' --max-amount 1000000

--max-amount is in USDC atomic units (1000000 = $1.00), so you can never pay more than you set.

Option B: any x402 client. Call the endpoint with no payment. You get HTTP 402 with the price in the body and a payment-required header. Sign the payment with your x402 client and retry. Settlement uses the Coinbase CDP facilitator on Base (eip155:8453).

Option C: MCP. Point an MCP client (streamable HTTP) at:

• https://claim-grounding.prospectintel.workers.dev/mcp
• https://prospect-intelligence.prospectintel.workers.dev/mcp

tools/list is free. Tool calls return x402 payment instructions; the paid HTTP route does the work.

Option D: pay by card (people). Stripe checkout, no wallet needed:

Product	Price	Link
Claim check	$0.50	https://buy.stripe.com/00w5kDcBN8ri9Go6NP0co02
Deep verify	$2.00	https://buy.stripe.com/9B614n1X9bDuf0I2xz0co06
Email lookup	$0.50	https://buy.stripe.com/4gMcN56dp36Y05O4FH0co05

Card prices are higher than agent prices because Stripe has a $0.50 minimum and per-charge fees.

Prices (USDC per call)

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

Method	Path	Price	What it does
POST	/v1/extract_claims	$0.05	Split text into checkable claims
POST	/v1/verify_claim	$1.00	Check one claim (Wikipedia)
POST	/v1/check_answer	$1.00	Split an AI answer into claims and check each (Wikipedia)
POST	/v1/deep_verify	$0.75	Check against six sources: Wikipedia, Wikidata, Google News titles, Europe PMC, FRED, SEC EDGAR. Async: poll GET /v1/jobs/:id (free)

Verdicts: supported, contradicted, outdated, mixed, insufficient_evidence.

Prospect Intelligence: https://prospect-intelligence.prospectintel.workers.dev

Method	Path	Price	What it does
POST	/v1/email	$0.08, charged only when an address is found	One work email for a name at a domain, with verification status, source and a send / send_with_caution / verify_first / do_not_send recommendation
POST	/v1/basic	$0.10	research_company
POST	/v1/enriched	$0.75	enrich_prospect
POST	/v1/tools	$0.75	Any one named tool: research_company, research_person, find_decision_makers, analyze_marketing_opportunity, identify_buying_signals, enrich_prospect, score_prospect, generate_prospect_brief
POST	/v1/deep	$3.00	Full prospect brief with a 0–90 score

Sample request and response

Request (real, paid, Oct 12, 2026):

npx awal@latest x402 pay https://claim-grounding.prospectintel.workers.dev/v1/verify_claim \
  -X POST -d '{"claim":{"text":"The Eiffel Tower is in Paris"}}'

Response (HTTP 200, shortened with …):

{
  "mode": "fast",
  "job_id": null,
  "claim": {
    "claim_id": "clm_14b3ffa736fd4fd1",
    "text": "The Eiffel Tower is in Paris",
    "span": { "start": 0, "end": 29 },
    "grounding_required": true,
    "verdict": "supported",
    "status_detail": "supported",
    "confidence": 0.95,
    "citations": [
      {
        "url": "https://en.wikipedia.org/wiki/Eiffel_Tower",
        "title": "Eiffel Tower",
        "quote": "The Eiffel Tower is a lattice tower on the …",
        "retrieved_at": "…",
        "provider": "wikipedia"
      }
    ],
    "rationale_short": "…"
  },
  "why": "…",
  "source": "https://en.wikipedia.org/wiki/Eiffel_Tower",
  "receipt": { "claim_hashes": ["sha256:…"], "evidence_urls": ["https://en.wikipedia.org/wiki/Eiffel_Tower"], "verdicts": ["supported"], "priced_usd": 1, "created_at": "…" }
}

Paid on Base: tx 0x839f…a901.

The unpaid first call (real, live) returns HTTP 402:

{
  "x402Version": 2,
  "error": "Payment required",
  "accepts": [{
    "scheme": "exact",
    "network": "eip155:8453",
    "amount": "80000",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "payTo": "0x485FfC037f02dDDc154A454a9cA89C4B1b29e25b",
    "maxTimeoutSeconds": 300,
    "extra": { "name": "USD Coin", "version": "2" }
  }]
}

(80000 = $0.08 for /v1/email. The asset is USDC on Base.)

Errors

Status	When	Charged?
200	Success	Yes
402	No or invalid payment. Body and payment-required header list what to pay	No
400	Bad input, e.g. missing claim.text, or mode: "deep" sent to verify_claim (use /v1/deep_verify). On email: missing domain or names	No
404	Email lookup found no address (no_result), unknown path, or unknown job id	No
405	Non-POST request to /mcp	No
409	Card payment already used for a lookup (one payment = one lookup)	No
422	Email provider rejected the input (e.g. domain has no mail records)	No
451	Email lookup: the person opted out of data processing. Do not contact or store	No
502 / 503	Upstream source or email provider unavailable. Safe to retry later	No

x402 only settles payment on a 2xx response, so failed calls cost nothing.

What these tools don't do

• Not legal, medical, financial or compliance advice. Not a certification.
• English only. Public sources only; no paywalled or private documents.
• Can return insufficient_evidence. Very recent news may lag.
• No guarantee an email is delivered or read. No personal/private emails, no phone numbers.
• Decision-makers are unknown unless a public source names them. Nothing is invented.

Discovery

/docs · /.well-known/x402 · /openapi.json · /llms.txt · /.well-known/mcp/server-card.json on each host. Listed on agentic.market.

Worker source stays private; this repo is the public surface for agents and builders.

Support

• Email: [email protected]
• Phone: (951) 234-7620
• Site: https://www.truepointmarketingpartners.com/ai-agent-tools