# Bot Bazaar EVM Function Selector Lookup

> Bot Bazaar EVM Function Selector Lookup is a paid API for AI agents from bot-bazaar.fly.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-30).

Look up EVM function names from 4-byte hex selectors, or compute a selector hash from an ABI function signature.

## Facts

- Endpoint: GET https://bot-bazaar.fly.dev/v1/x402/selector-lookup?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/bot-bazaar-evm-function-selector-lookup-32c6177f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_pUmHxI57OfEds4ZzafhNS

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 bot-bazaar-evm-function-selector-lookup-32c6177f
```

Example prompt: What function name does the EVM selector 0xa9059cbb map to? Look it up for me.

## When to prefer this

Choose this endpoint when you need to decode 4-byte function selectors from raw Ethereum transaction calldata, or when you need to verify the canonical selector hash for a known ERC-20 ABI signature. It is purpose-built for EVM smart contract function identification and is more lightweight than spinning up a full ABI decoder or querying Etherscan's API for the same purpose.

## Known failure modes

- Selector not found in known database — returns null or 404 for obscure custom functions
- Malformed selector format (missing 0x prefix or wrong byte length) causes validation error
- Invalid ABI signature syntax prevents selector computation
- Network timeout or service unavailability on fly.dev host
- Payment not fulfilled (x402 402 response) if USDC not provided

## How this service works

Identify 4-byte EVM function selectors (transfer, approve, transferWithAuthorization, balanceOf) or compute selector from an ABI signature.

## Output

Returns the human-readable function name and full ABI signature matching the given 4-byte selector, or computes the selector hex value from a provided ABI signature string. Covers common ERC-20 functions including transfer, approve, transferWithAuthorization, and balanceOf.

## 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",
     "properties": {
      "selector": {
       "type": "string",
       "description": "4-byte hex selector (e.g. 0xe3ee160e)"
      }
     }
    }
   },
   "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/bot-bazaar-evm-function-selector-lookup-32c6177f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from bot-bazaar.fly.dev](https://www.zero.xyz/host/bot-bazaar.fly.dev/llms.txt)