# Anchor X402 Yes/No Oracle

> Anchor X402 Yes/No Oracle is a paid API for AI agents from api.anchor-x402.com, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-13).

Answers a yes/no question with a cryptographically-signed verdict anchored to both Base and Solana mainnet blockchains

## Facts

- Endpoint: POST https://api.anchor-x402.com/v1/oracle
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-anchor-x402-com-6b54f158
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_bmZPzdXdXH0eBvS8pR9aa

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 api-anchor-x402-com-6b54f158 -d '<json body>'
```

Example prompt: Can you get a yes/no oracle verdict on whether this wallet address has been active in the last 30 days, and anchor the signed decision to both Base and Solana so I have an immutable on-chain proof?

## When to prefer this

Use this endpoint when you need a tamper-proof, auditable yes/no answer that must be independently verifiable on-chain. Ideal for smart contract triggers, compliance checks, dispute resolution, or any workflow requiring a cryptographic proof of a boolean decision backed by dual-chain anchoring on both Base and Solana.

## Known failure modes

- Ambiguous question that cannot be resolved to a boolean — returns 4xx with an error message
- Payment failure or insufficient USDC balance — returns 402 Payment Required
- Network or RPC failure on Base or Solana during anchoring — partial anchor with error details
- Rate limiting or quota exceeded — returns 429
- Malformed request body — returns 400 with validation details

## How this service works

Yes/no oracle with dual-chain anchored verdict (Base + Solana). $0.05 USDC.

## Output

A signed yes/no verdict with the decision anchored on both Base and Solana mainnet, returning the boolean answer, transaction hashes for both chains, a cryptographic signature over the (input_hash, output_hash, decision) tuple, and a timestamp.

## Example request

```json
{
 "question": "Is artificial intelligence beneficial to society?"
}
```

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "required": [
      "question"
     ],
     "properties": {
      "question": {
       "type": "string",
       "maxLength": 1000,
       "description": "A yes/no question for the oracle."
      }
     }
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST",
      "PUT",
      "PATCH"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "answer": "MAYBE",
  "base_tx": "0x7fb4d107d8c1b65b33851434c6fd178b682a143904a2bfa89ff2c1fa70974e96",
  "asked_at": 1746820000,
  "solana_tx": "u8rqU4oSQkkHQw93nCCtQym5crh4UjuoNvYhspLcUTEny59asrNNffpmxpgzRuZ4MXQnN5UEoCKQuDS16ZMPKW2",
  "explanation": "Possible if you cut the bottom three items and stop opening Twitter.",
  "merkle_root": "ab0898397c86fbf97c99c6f8b29e55ab697315705777ee1d106e2dcb9bd686b3"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-anchor-x402-com-6b54f158/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.anchor-x402.com](https://www.zero.xyz/host/api.anchor-x402.com/llms.txt)