# X402 Asset Match

> X402 Asset Match is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Compares a challenge asset identifier against a list of buyer-supported assets and returns an explicit accept/reject verdict with mismatch reasons and normalized evidence.

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/x402-asset-match
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-asset-match-a23f7589
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_MMQ_LJ0uRxQvZYJR_kV0F

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-asset-match-a23f7589 -d '<json body>'
```

Example prompt: Before we pay this x402 invoice, check if the challenge asset '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48' matches our supported assets list ['0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48', '0xdAC17F958D2ee523a2206206994597C13D831ec7'] and tell me if it's safe to proceed.

## When to prefer this

Choose this endpoint when you need a deterministic, stateless, in-memory asset compatibility check within an x402 payment or agent delivery flow — especially when you want an explicit accept/reject verdict with structured mismatch reasoning rather than writing your own comparison logic. Prefer this over ad-hoc string matching when you need versioned, auditable evidence of the comparison decision.

## Known failure modes

- Asset string exceeds 8192 character limit — request rejected
- Supported assets array exceeds 256 items — request rejected
- Malformed or non-string asset identifier — validation error returned
- Empty supported_assets array — likely results in rejection with mismatch reason
- Missing required 'asset' field — schema validation error

## How this service works

X402 Asset Match: X402 Asset Match compares a challenge asset identifier with buyer-supported assets from bounded caller-supplied values without an external provider. Call X402 Asset Match before paying for or accepting an x402 or agent delivery assembled from caller-supplied challenge and result metadata. Returns contract-specific checks, normalized evidence, mismatch reasons, and an explicit acceptance or rejection status for X402 Asset Match as versioned deterministic JSON. Price: $0.001 USD…

## Output

Returns versioned deterministic JSON containing an explicit accept or reject status, contract-specific checks, normalized evidence of the comparison, and detailed mismatch reasons explaining why the asset was or was not accepted.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "asset": {
   "type": "string",
   "maxLength": 8192,
   "description": "Asset supplied to X402 Asset Match; used only for this bounded calculation and processed in memory without retention."
  },
  "supported_assets": {
   "type": "array",
   "items": {
    "type": "string",
    "maxLength": 8192
   },
   "maxItems": 256,
   "description": "Supported Assets supplied to X402 Asset Match; used only for this bounded calculation and processed in memory without retention."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "actual": "USDC",
   "matched": true,
   "supported": [
    "USDC"
   ]
  },
  "schema": "delx/util-x402-asset-match/v1",
  "status": "pass",
  "evidence": {
   "retained": false,
   "input_sha256": "87c9c6183983f222462f4ce259bafbeb4418e6ba18af409b98db69898b5ce097",
   "external_calls": 0
  },
  "operation": "delivery_contract:x402_asset_match"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-asset-match-a23f7589/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.delx.ai](https://www.zero.xyz/host/api.delx.ai/llms.txt)