# Tollkit Chain Token Attestation Check

> Tollkit Chain Token Attestation Check is a paid API for AI agents from attest.tollkit.dev, paid per call via x402, $0.004/call, status unknown (last checked 2026-10-11).

Checks/attests a token contract address on a specified blockchain (Base, Ethereum, or Solana) and returns on-chain verification data, paid per-call via x402 in USDC.

## Facts

- Endpoint: POST https://attest.tollkit.dev/chain/check?utm_source=zero.xyz
- Price: $0.004/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/tollkit-chain-token-attestation-check-98780b8d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_jpq7imX_0djpVCPbulU_b

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 tollkit-chain-token-attestation-check-98780b8d -d '<json body>'
```

Example prompt: Can you attest the token contract 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 on Ethereum and tell me if it checks out?

## When to prefer this

Use this endpoint when you need a frictionless, pay-per-call on-chain token attestation with no account setup — ideal for agents that encounter unknown token addresses and need instant verification on Base, Ethereum, or Solana without managing API subscriptions. Prefer this over traditional token-info APIs when you want x402 micropayment billing and multi-chain coverage in a single call.

## Known failure modes

- Invalid token address format (must match ERC-20 0x hex or SPL base58 pattern) — returns validation error
- Unsupported chain value — only 'base', 'ethereum', or 'solana' accepted
- Payment failure via x402 (insufficient USDC balance or unsupported payment chain) — returns 402 Payment Required
- Token contract not found on specified chain — returns empty or not-found attestation
- Network or RPC timeout when querying chain data

## How this service works

Pay-per-call product page extraction. No account, no API key: pay in-band with x402 in USDC on Base or Solana.

## Output

Returns an attestation or verification result for the given token contract address on the specified chain — including whether the token is recognized, any on-chain metadata, and verification signals. Paid per-call at $0.004 USDC via x402 with no account or API key required.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "chain": {
   "enum": [
    "base",
    "ethereum",
    "solana"
   ],
   "type": "string",
   "default": "base",
   "description": "Which chain to read: \"base\" (default), \"ethereum\" or \"solana\"."
  },
  "token": {
   "type": "string",
   "pattern": "^(0x[0-9a-fA-F]{40}|[1-9A-HJ-NP-Za-km-z]{32,44})$",
   "description": "ERC-20 contract or SPL mint."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/tollkit-chain-token-attestation-check-98780b8d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from attest.tollkit.dev](https://www.zero.xyz/host/attest.tollkit.dev/llms.txt)