# Delx X402 Discovery Parity Check

> Delx X402 Discovery Parity Check is a paid API for AI agents from commerce.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-02).

Verifies that tool lists across catalog, OpenAPI, runtime, and portfolio sources are consistent and complete, returning a parity result with missing tool details.

## Facts

- Endpoint: POST https://commerce.delx.ai/api/v1/x402/x402-discovery-parity-check?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-x402-discovery-parity-check-7fa7c61e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_uAQSbYbT4OeTxDmFzQT0e

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 delx-x402-discovery-parity-check-7fa7c61e -d '<json body>'
```

Example prompt: Check if my agent's tools are in parity across all four discovery sources — I have these catalog tools: ['tool-a', 'tool-b'], OpenAPI tools: ['tool-a', 'tool-b'], runtime tools: ['tool-a', 'tool-b'], and portfolio tools: ['tool-a', 'tool-b']. Tell me what's missing from any source and whether they all match.

## When to prefer this

Use this endpoint when you need a cryptographically-verifiable, stateless parity check across x402 tool discovery sources (catalog, OpenAPI, runtime, portfolio) with proof of no data retention. Prefer it over manual diffing or custom scripts when you need a structured missing-tools report per source and an auditable SHA256 input hash for compliance or debugging.

## Known failure modes

- Malformed array items exceeding 8192 characters return validation errors
- Exceeding 256 items per array may result in rejection
- Empty arrays may produce trivially-passing parity that masks real gaps
- Payment failure via x402 returns 402 before processing begins

## How this service works

Pay-per-result APIs for agents. No signup. Exact price. Verifiable delivery. USDC on Base + Solana via x402.

## Output

Returns a JSON object with counts of tools per source, a boolean parity flag indicating whether all sources are in sync, and a 'missing' breakdown per source listing any absent tools. Also includes an evidence block with the input SHA256 hash, a retained=false flag confirming no data retention, and the operation name.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "catalog_tools": {
   "type": "array",
   "items": {
    "type": "string",
    "maxLength": 8192
   },
   "maxItems": 256,
   "description": "Catalog Tools supplied to X402 Discovery Parity Check; used only for this bounded calculation and processed in memory without retention."
  },
  "openapi_tools": {
   "type": "array",
   "items": {
    "type": "string",
    "maxLength": 8192
   },
   "maxItems": 256,
   "description": "Openapi Tools supplied to X402 Discovery Parity Check; used only for this bounded calculation and processed in memory without retention."
  },
  "runtime_tools": {
   "type": "array",
   "items": {
    "type": "string",
    "maxLength": 8192
   },
   "maxItems": 256,
   "description": "Runtime Tools supplied to X402 Discovery Parity Check; used only for this bounded calculation and processed in memory without retention."
  },
  "portfolio_tools": {
   "type": "array",
   "items": {
    "type": "string",
    "maxLength": 8192
   },
   "maxItems": 256,
   "description": "Portfolio Tools supplied to X402 Discovery Parity Check; used only for this bounded calculation and processed in memory without retention."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "counts": {
    "catalog": 2,
    "openapi": 2,
    "runtime": 2,
    "portfolio": 2
   },
   "parity": true,
   "missing": {
    "catalog": [],
    "openapi": [],
    "runtime": [],
    "portfolio": []
   }
  },
  "schema": "delx/util-x402-discovery-parity-check/v1",
  "status": "pass",
  "evidence": {
   "retained": false,
   "input_sha256": "2a4e869067b7be7349f2d8d258047e08b504e1fc708e4bef33d84574262c87f4",
   "external_calls": 0
  },
  "operation": "delivery_contract:x402_discovery_parity_check"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-x402-discovery-parity-check-7fa7c61e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from commerce.delx.ai](https://www.zero.xyz/host/commerce.delx.ai/llms.txt)