Keys & pricing

What each call costs #

Every endpoint page and every row of the API overview shows its price. The MCP tools cost the same as the REST call behind them. A call that fails costs nothing. Current prices and the seller address are always published at /v1/status.

API keys and credits #

1. Sign in

   At coingraph.ai/signin, with Google, a one-time email code or an Ethereum wallet. Every account starts on the Free plan: 500 credits to start, no monthly refill. Accounts opened with Google or email by 30 November 2026 get 500 more that never expire. Wallet accounts get the starter credits only, and temporary email addresses get none.

2. Create a key

   On Account → API keys. The full key (cg_live_…) is shown once; store it as a secret and never commit it.

3. Send it on every paid call

   cURL

   Copy

   curl -X POST "https://coingraph.ai/api/v1/evaluate" \
     -H "Authorization: Bearer $COINGRAPH_KEY" \
     -H "content-type: application/json" \
     -d '{"token":"solana","size_usd":5000}'

Every response says what it cost and what is left in the x-credits-charged and x-credits-remaining headers. Monthly credits are spent first, then top-up credits, which never expire. Usage per day and endpoint: Account → Usage.

Plans and top-ups #

Plans, what 1,000 credits buy and the refund policy: Pricing. Webhook monitors are part of Pro and above.

Pay per call with x402 #

An autonomous agent can pay for each answer itself, with no account and no key. x402 uses the HTTP status 402 Payment Required; the agent needs a wallet on a supported network. Cardano is supported today and more networks are coming.

1. Call the endpoint

   Without payment, a paid endpoint answers 402. The PAYMENT-REQUIRED header (base64 JSON) says what to pay, in what asset, and to which address; the body repeats it in plain words. The exact body is on Errors & limits.

2. Pay

   The agent builds and signs a transaction for the exact amount, but does not broadcast it. @x402/fetch with @x402/cardano does this automatically within a spending cap you set.

3. Retry with the signed payment

   The agent repeats the request with the PAYMENT-SIGNATURE header. CoinGraph's facilitator verifies the transaction, the answer is computed, the facilitator broadcasts the payment, and the answer is released with a PAYMENT-RESPONSE receipt carrying the transaction id.

{
  "x402Version": 2,
  "error": "Payment required",
  "resource": {
    "url": "https://coingraph.ai/api/v1/agents/trade-gatekeeper",
    "description": "Run a CoinGraph agent (Premium tier, 5 tADA)",
    "mimeType": "application/json",
    "serviceName": "CoinGraph"
  },
  "accepts": [
    {
      "scheme": "exact",
      "network": "cardano:preprod",
      "amount": "5000000",
      "asset": "lovelace",
      "payTo": "addr_test1…",
      "maxTimeoutSeconds": 600,
      "extra": {
        "confirmationPolicy": {
          "l1Confirmations": -1
        }
      }
    }
  ]
}

{
  "success": true,
  "payer": "addr_test1qrwcm2ks…szndmw",
  "transaction": "d3a147217859d56695edf6135e4c34c5b483efa120052e7bde4215b39bd1d477",
  "network": "cardano:preprod",
  "extra": {
    "status": "mempool",
    "confirmations": -1
  }
}

A whole round trip takes a few seconds. That transaction on Cardanoscan. The facilitator is not custodial: it only verifies and broadcasts a transaction the agent has already signed, and never holds funds. CoinGraph releases the answer once the node has accepted the payment (l1Confirmations: -1).

Pay from code #

npm install @x402/fetch@2.26.0 @x402/cardano@2.26.0 @x402/core@2.26.0

The same buyer is in the repository as scripts/x402-buyer.ts:

npx tsx scripts/x402-buyer.ts https://coingraph.ai trade-gatekeeper '{"token":"chainlink","size_usd":5000}'

MCP spends the same credits #

Add https://coingraph.ai/mcp to your AI tool. The first time, it opens a CoinGraph sign-in (OAuth); tool calls then spend your account's credits at the prices above. Code that cannot open a sign-in window sends a key as Authorization: Bearer cg_live_… instead. Setup per tool: Connect.

Free allowances #

What is live today #

Whichever path you pay by, the same engine answers, so a verdict seen in Claude, paid for with credits or x402, or delivered on Sokosumi can be proved at the same proof link.