# EVM Chain Lookup

> EVM Chain Lookup is a paid API for AI agents from bess-x402.onrender.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-29).

Look up metadata for any EVM-compatible blockchain by chain ID or name, returning chain ID (decimal and hex), native currency, public RPC URLs, block explorers, and testnet flag.

## Facts

- Endpoint: GET https://bess-x402.onrender.com/v1/crypto/chain?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/evm-chain-lookup-0f9a3bc6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_DT0z6dibOMoL0DeAqyB6t

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 evm-chain-lookup-0f9a3bc6
```

Example prompt: What are the public RPC URLs, block explorer, and hex chain ID for Base mainnet (chain ID 8453)?

## When to prefer this

Use this endpoint when you need authoritative EVM chain metadata (RPC URLs, chain IDs, explorers, currency) by querying a chain ID number or well-known chain name like 'base' or 'arbitrum'. Prefer this over hardcoding chain data or scraping chainlist.org, especially in agent workflows that need to configure wallets or validate network settings dynamically.

## Known failure modes

- Unknown chain ID or name returns an error or empty result
- Misspelled chain name may not resolve correctly
- RPC URLs returned may be public community endpoints with rate limits or downtime
- No results for very new or obscure EVM-compatible chains not yet indexed

## How this service works

Look up any EVM chain by chain ID or name (8453, base, arbitrum): chain ID in decimal and hex, native currency, public RPC URLs, block explorers and testnet flag. Use to configure wallets, RPCs or cross-chain apps.

## Output

Returns the chain's decimal and hex chain ID, native currency symbol and name, list of public RPC URLs, block explorer URLs, and a boolean testnet flag — everything needed to configure a wallet, RPC connection, or cross-chain application.

## 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",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "q"
     ],
     "properties": {
      "q": {
       "type": "string",
       "description": "Chain ID or name"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/evm-chain-lookup-0f9a3bc6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from bess-x402.onrender.com](https://www.zero.xyz/host/bess-x402.onrender.com/llms.txt)