# x402 Bazaar: Base Transaction Explainer (AI-Powered)

> x402 Bazaar: Base Transaction Explainer (AI-Powered) is a paid API for AI agents from api.relai.fi, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Takes a Base blockchain transaction hash and returns a plain-English explanation of what the transaction actually did, including a risk assessment and contextual notes.

## Facts

- Endpoint: POST https://api.relai.fi/relay/1782567677091/api/x402/ai-tx-explain
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-bazaar-base-transaction-explainer-ai-powered-cc1dd13b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_7R-xJDpIxThadgeAQdkfP

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 x402-bazaar-base-transaction-explainer-ai-powered-cc1dd13b -d '<json body>'
```

Example prompt: Can you explain what this Base transaction actually did and whether it looks risky? The hash is 0x4a3f2b1c9d8e7f6a5b4c3d2e1f0a9b8c7d6e5f4a3b2c1d0e9f8a7b6c5d4e3f2a.

## When to prefer this

Choose this endpoint when you need a human-readable explanation of a specific Base network transaction — especially when you have only the transaction hash and need to understand intent, risk, and context without manually decoding ABI calldata. Ideal for agents helping users audit their wallet history, flag suspicious activity, or understand DeFi interactions they participated in. Prefer this over generic block explorers when a risk-labeled, narrative summary is needed rather than raw data.

## Known failure modes

- Invalid or non-existent transaction hash returns an error
- Transaction not found on Base mainnet
- Payment not provided upfront returns HTTP 402 with payment requirements (must pay $0.03 USDC on Base to address 0x973a31858f4d2125f48c880542da11a2796f12d6 and retry)
- Malformed POST body or missing transaction hash field
- Upstream Claude API timeout or unavailability

## How this service works

Give a Base transaction hash and Claude explains what it actually did in plain English — the action, a risk read (failed tx, risky approval, high-value transfer), and notes. Turns raw calldata into an answer agents and humans can use. Paid via x402: $0.03 in USDC on Base (eip155:8453) to 0x973a31858f4d2125f48c880542da11a2796f12d6. Returns 402 with payment requirements; pay and retry.

## Output

A structured response containing: (1) a plain-English description of the transaction action (e.g. swap, transfer, approval, contract call), (2) a risk read categorizing the transaction as failed, risky approval, high-value transfer, or benign, and (3) additional notes and context for the transaction. Useful for both human users and AI agents trying to understand on-chain activity.

## 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"
    },
    "pathParams": {
     "type": "object"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "hash"
     ],
     "properties": {
      "hash": {
       "type": "string",
       "description": "Transaction hash"
      }
     }
    }
   },
   "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/x402-bazaar-base-transaction-explainer-ai-powered-cc1dd13b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.relai.fi](https://www.zero.xyz/host/api.relai.fi/llms.txt)