# payable.nsgoods.org x402 Payability Checker

> payable.nsgoods.org x402 Payability Checker is a paid API for AI agents from payable.nsgoods.org, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Checks whether a given URL is a valid, reachable x402 payable endpoint by verifying HTTP 402 response, well-formed payment headers, and Solana destination ATA existence

## Facts

- Endpoint: GET https://payable.nsgoods.org/payable
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/payable-nsgoods-org-x402-payability-checker-aeaf3b70
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_yRtulQoSScY4295lyCNJO

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 payable-nsgoods-org-x402-payability-checker-aeaf3b70
```

Example prompt: Before I try to pay it, can you check whether https://api.example.com/data is a properly configured x402 payable endpoint — confirm it's reachable, returns a real 402, accepts well-formed payment requests, and has a valid Solana destination?

## When to prefer this

Use this endpoint when you need to verify that a URL is correctly configured as an x402 payable endpoint before committing a payment, listing it in a marketplace, or integrating it into an agent workflow. It is specifically valuable for Solana-based x402 payments because it also checks on-chain ATA existence, not just the HTTP layer. Prefer this over generic HTTP probing tools when you need a signed, structured attestation of x402 compliance rather than a raw HTTP response.

## Known failure modes

- Endpoint URL is unreachable or times out — verdict returned as non-payable with reachable=false
- Endpoint returns 402 but with malformed payment headers — accepts_wellformed=false
- Solana destination ATA does not exist on-chain — payable_networks excludes Solana
- Invalid or non-HTTP URL provided as resource parameter — input validation error
- Target endpoint returns unexpected status code (200, 404, 500) instead of 402

## How this service works

x402 payability check: reachable + well-formed 402 + (Solana) destination-ATA existence

## Output

Returns a structured JSON attestation including: overall payability verdict (pass/fail), whether the endpoint is reachable, whether it returns an HTTP 402, whether it accepts well-formed payment requests, a list of payable networks (e.g. Solana), payment options with destination addresses and details, a schema version, the checked timestamp, and a cryptographic signature from the checker service attesting to the result.

## 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": [
      "resource"
     ],
     "properties": {
      "resource": {
       "type": "string",
       "description": "https URL of an x402 endpoint to check for payability."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "schema_version",
      "resource",
      "verdict",
      "options",
      "payable_networks",
      "signed_by",
      "signature"
     ],
     "properties": {
      "method": {
       "enum": [
        "GET",
        "POST",
        null
       ],
       "type": [
        "string",
        "null"
       ]
      },
      "reason": {
       "type": [
        "string",
        "null"
       ]
      },
      "options": {
       "type": "array",
       "items": {
        "type": "object",
        "properties": {
         "asset": {
          "type": [
           "string",
           "null"
          ]
         },
         "amount": {
          "type": [
           "string",
           "integer",
           "null"
          ]
         },
         "detail": {
          "type": "object"
         },
         "pay_to": {
          "type": "string"
         },
         "scheme": {
          "type": [
           "string",
           "null"
          ]
         },
         "network": {
          "type": "string"
         },
         "verdict": {
          "type": "string"
         },
         "facilitator": {
          "type": [
           "object",
           "null"
          ]
         },
         "maxTimeoutSeconds": {
          "type": [
           "integer",
           "null"
          ]
         }
        }
       }
      },
      "verdict": {
       "type": "string"
      },
      "resource": {
       "type": "string"
      },
      "reachable": {
       "type": "boolean"
      },
      "signature": {
       "type": "string"
      },
      "signed_by": {
       "type": "string"
 
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/payable-nsgoods-org-x402-payability-checker-aeaf3b70/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from payable.nsgoods.org](https://www.zero.xyz/host/payable.nsgoods.org/llms.txt)