# AgentIndex x402 Tip Endpoint

> AgentIndex x402 Tip Endpoint is a paid API for AI agents from x402.agentindex.world, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-11).

Accepts a micropayment tip via x402/USDC on Base and echoes back a payment receipt with payer, network, and request metadata.

## Facts

- Endpoint: GET https://x402.agentindex.world/tip?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentindex-x402-tip-endpoint-5d594195
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_idUCGpu3LZbqLk8p9dciS

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 agentindex-x402-tip-endpoint-5d594195
```

Example prompt: Send a $0.01 USDC tip to AgentIndex on Base using x402 and echo back 'hello agent' so I can confirm the payment went through.

## When to prefer this

Use this endpoint to test or demonstrate x402 micropayment settlement on Base mainnet, confirm wallet and payment infrastructure is working, or send a small tip to AgentIndex. It is the simplest x402 endpoint available — not for data retrieval or AI tool calls.

## Known failure modes

- Payment not settled: returns 402 if x402 payment header is missing or insufficient
- Invalid method: only GET, HEAD, DELETE are accepted
- Insufficient USDC balance: payment fails at the facilitator level
- Network mismatch: payment on wrong chain results in rejection
- Malformed query params: unexpected fields rejected due to strict schema

## How this service works

Pay-per-call tools for AI agents: web search + content, documents, live market data, and multi-chain wallet/gas reads. Mainnet test from $0.000001 USDC on Base. Pay-per-call tools for AI agents in USDC on Base (x402/MPP): search, pdf, web-read, extract, summarize, fact-check, translate, jobs, discover. See GET /capabilities.

## Output

Returns a JSON object with ok (boolean), payer wallet address, network (eip155:8453 for Base), purpose string, price in USDC and atomic units, an x402 receipt object, and an echo of any message or request fields sent.

## 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": [],
     "properties": {
      "message": {
       "type": "string",
       "description": "Optional test message to echo after successful settlement."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "ok",
      "purpose",
      "network",
      "price_usdc",
      "price_atomic_usdc",
      "request"
     ],
     "properties": {
      "ok": {
       "type": "boolean"
      },
      "payer": {
       "type": [
        "string",
        "null"
       ]
      },
      "network": {
       "type": "string"
      },
      "purpose": {
       "type": "string"
      },
      "request": {
       "type": "object"
      },
      "price_usdc": {
       "type": "number"
      },
      "x402_receipt": {
       "type": "object"
      },
      "price_atomic_usdc": {
       "type": "string"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "payer": "0xb3F32bdfe8D07825BC0D7387295aB1D7559BA69d",
  "network": "eip155:8453",
  "purpose": "support-agentindex",
  "request": {
   "echo": {
    "hello": "agent"
   },
   "method": "POST"
  },
  "price_usdc": 0.01,
  "price_atomic_usdc": "10000"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentindex-x402-tip-endpoint-5d594195/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.agentindex.world](https://www.zero.xyz/host/x402.agentindex.world/llms.txt)