for AI agents · MCP + REST

Verify a claim.
Get a verdict backed by a real quote.

POST one factual claim. We search the live web, extract the sources, adjudicate, and return supported / refuted / insufficient_evidence — with the exact verbatim passage the verdict came from. $0.02 per verified claim, billed only on success.

Get an API key See the response

Request

curl https://api.verify-api.dev/v1/verify \
  -H "Authorization: Bearer csk_live_..." \
  -H "Idempotency-Key: 018f4c8a-1234-4321-abcd-e3f6a7b8c9d0" \
  -d '{"claim":"The iPhone 15 launched on September 22, 2023."}'

Response

{
  "verdict": "supported",
  "confidence": 0.97,
  "source_url": "https://www.apple.com/newsroom/2023/09/...",
  "published_date": "2023-09-12",
  "exact_quote": "iPhone 15 and iPhone 15 Plus will be available … on Friday, September 22.",
  "cache": "miss",
  "billed_usd": 0.02
}

Try it before you sign up

No account, no key, no card. POST /v1/verify/trial from anywhere, rate-limited per IP. Same verdict shape, same signed receipt.

One curl — no auth

curl -X POST https://api.verify-api.dev/v1/verify/trial \
  -H "Content-Type: application/json" \
  -d '{"claim":"The iPhone 15 launched on September 22, 2023."}'

Verdicts, not documents

Everyone else returns pages. We return a decision — with a quote you can show your user.

Billed only on success

insufficient_evidence, out_of_scope, and malformed are free. Our incentives are aligned with yours.

Verbatim-quote gate

Every verdict includes text that appears character-for-character in the cited source. No hallucinated citations, by construction.

Works everywhere agents live

Native REST for programmatic callers, MCP server for Claude Desktop, Cursor, Windsurf, ChatGPT Desktop, and any MCP-capable host.

One line of pricing.

$0.02 per verified claim

Prepaid balance, top up any amount ≥ $5
Free: insufficient_evidence, out_of_scope, malformed
Semantic cache hits still count as billable if we return a verdict
No seats, no monthly minimum, no rate-limit tiers

Start with $5

Drop-in for MCP clients.

Add one block to your MCP config and the model gets a verify_claim tool alongside its other tools. Works with Claude Desktop, Cursor, Windsurf, VS Code Copilot agent mode, and any other MCP-capable host.

{
  "mcpServers": {
    "verifyapi": {
      "command": "npx",
      "args": ["-y", "@verify-api/mcp"],
      "env": { "VERIFYAPI_API_KEY": "csk_live_..." }
    }
  }
}

Get an API key. Instantly.

One POST, no email, no waitlist, no card. Free trial calls with no key at /v1/verify/trial, or grab a key here and top up when you're ready. Same endpoint, whether you're an agent, a script, or a human.

Agent-native — one curl

curl -X POST https://api.verify-api.dev/v1/accounts \
  -H "Content-Type: application/json" \
  -d '{"source":"curl"}'

Response includes api_key (shown once — save it). Balance starts at $0 — top up any amount, or use the free trial endpoint first.

Limit: 3 signups per IP per day. If you hit that, wait 24h or use /v1/verify/trial in the meantime.

Top up your balance

Add credit via Stripe Checkout — pay-as-you-go, no minimums past $1, no expiry. Cache hits within your account are always free.

One-click preset ($10 / $50 / $200 / $1,000)

curl -X POST https://api.verify-api.dev/v1/balance/topup/preset \
  -H "Authorization: Bearer csk_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "tier": "50",
    "success_url": "https://your-app.example/topup/done",
    "cancel_url":  "https://your-app.example/topup/cancel"
  }'

Returns {checkout_url, session_id}. Redirect the user to checkout_url. Valid tier values are the strings "10", "50", "200", "1000" (dollar amounts).

Custom amount

curl -X POST https://api.verify-api.dev/v1/balance/topup \
  -H "Authorization: Bearer csk_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "amount_usd": 25,
    "success_url": "https://your-app.example/topup/done",
    "cancel_url":  "https://your-app.example/topup/cancel"
  }'

All three fields are required. amount_usd must be a positive number ≥ the server minimum (currently $1).

For long-running agents, enable auto-refill in the dashboard — save a card once, never get stuck mid-task on an empty balance.

Verify a claim.Get a verdict backed by a real quote.