base-contract-state

Inspect whether a Base address currently has deployed bytecode and return code size plus best-effort ERC-20 metadata.

Price: $0.01 USDC equivalent
Endpoint: POST /v1/base-contract-state
Network: Base mainnet · eip155:8453
Asset: USDC
MCP tool: base-contract-state
External payability: PASS · 2026-10-08T19:55:01.298Z

When an agent should use it

is this address a contract on Base
Base smart contract metadata
inspect token contract state without API key

Input schema

{
  "type": "object",
  "properties": {
    "address": {
      "type": "string",
      "pattern": "^0x[0-9a-fA-F]{40}$"
    }
  },
  "required": [
    "address"
  ],
  "additionalProperties": false
}

Example request

{
  "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
}

Example output

{
  "is_contract": true,
  "code_bytes": 1234,
  "token": {
    "symbol": "USDC",
    "decimals": 6
  },
  "block_number": 12345678
}

x402 flow

POST /v1/base-contract-state
→ HTTP 402 + PAYMENT-REQUIRED
→ buyer authorizes locally
→ retry same request with PAYMENT-SIGNATURE
→ one governed execution + machine-readable JSON

Discovery: OpenAPI · x402 · llms.txt

A valid 402/payability probe is operational evidence, not proof of independent demand, future settlement, or semantic correctness.