# Circle CCTP Cross-Chain Transfer Fee Lookup

> Circle CCTP Cross-Chain Transfer Fee Lookup is a paid API for AI agents from api.chainmarket-api.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-24).

Returns Circle CCTP (Cross-Chain Transfer Protocol) fee tiers and fast-burn allowance for USDC transfers between two specified blockchain domains

## Facts

- Endpoint: GET https://api.chainmarket-api.workers.dev/api/crypto/circle-cctp-transfers?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-24
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/circle-cctp-cross-chain-transfer-fee-lookup-52ccd286
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_pJ8Uoq6OEfJuq_HwtSlNu

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability circle-cctp-cross-chain-transfer-fee-lookup-52ccd286
```

Example prompt: What are the current Circle CCTP fee tiers and fast burn allowance for bridging USDC from Ethereum (domain 0) to Base (domain 6)?

## When to prefer this

Use this endpoint when you need to programmatically check Circle CCTP fee tiers and fast burn allowance before executing a USDC cross-chain transfer, especially to determine which fee tier applies based on finality thresholds. Prefer this over manually querying Circle's iris-api directly when you want a pay-per-call, no-signup abstraction with multi-chain payment support.

## Known failure modes

- Invalid or unsupported domain ID returns an error or empty response
- Network timeout if Circle's iris-api.circle.com is unreachable
- Payment failure if insufficient USDC balance for the $0.002 per-call fee
- Stale data if Circle's allowance endpoint has not updated recently

## How this service works

Circle CCTP (USDC cross-chain transfer) fast-burn allowance and the fee tiers for one source-to-destination domain pair. Narrowed: the attestation status of a specific transfer needs its burn transaction hash, which this tool does not take, so per-transfer attestation is not reported.

## Output

Returns a JSON object containing the data source URL, an array of fee tiers (each with minimumFeeBps and finalityThreshold), the fast burn allowance in USDC, the source and destination domain IDs, and timestamps for when the data was checked and when the allowance was last updated.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [],
     "properties": {
      "source": {
       "type": "string",
       "description": "CCTP source domain id, e.g. 0 = Ethereum (default 0)"
      },
      "destination": {
       "type": "string",
       "description": "CCTP destination domain id, e.g. 6 = Base (default 6)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "source": "https://iris-api.circle.com/v2/burn/USDC/fees/0/6",
  "feeTiers": [
   {
    "minimumFeeBps": 1,
    "finalityThreshold": 1000
   },
   {
    "minimumFeeBps": 0,
    "finalityThreshold": 2000
   }
  ],
  "checkedAt": "2026-10-23T09:36:06.160Z",
  "sourceDomain": 0,
  "destinationDomain": 6,
  "allowanceUpdatedAt": "2026-10-23T09:36:05.104Z",
  "fastBurnAllowanceUsdc": 52430875.401937
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/circle-cctp-cross-chain-transfer-fee-lookup-52ccd286/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.chainmarket-api.workers.dev](https://www.zero.xyz/host/api.chainmarket-api.workers.dev/llms.txt)