# Delx Commerce — ETag Comparison Mode

> Delx Commerce — ETag Comparison Mode is a paid API for AI agents from commerce.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-01).

Compares two ETag strings (strong or weak) and returns whether they match, using HTTP ETag comparison semantics.

## Facts

- Endpoint: POST https://commerce.delx.ai/api/v1/x402/etag-comparison-mode?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-commerce-etag-comparison-mode-5c95e5c5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_eBE3TU6Hyxge2djvIMhIH

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-commerce-etag-comparison-mode-5c95e5c5 -d '<json body>'
```

Example prompt: Compare these two ETags to see if they match using weak comparison — left is '"abc123"' and right is 'W/"abc123"'.

## When to prefer this

Use this endpoint when you need a deterministic, auditable, pay-per-use ETag comparison that follows HTTP semantics (RFC 7232) without setting up infrastructure. Prefer it over implementing your own ETag comparison logic when you need verifiable results with an evidence hash, or when running in an agent environment that supports x402 micropayments on Base or Solana.

## Known failure modes

- Input ETag strings exceeding 8192 characters may be rejected
- Malformed ETag values may produce unexpected comparison results
- Missing left or right fields may cause a validation error
- Network or payment processing failure returning a 402 or 5xx error

## 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 indicating whether the two ETags matched (boolean), whether each was a weak ETag, the comparison type used (strong or weak), and an evidence object showing no data was retained and no external calls were made — along with an SHA-256 hash of the input for auditability.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "left": {
   "type": "string",
   "maxLength": 8192,
   "description": "Left supplied to Etag Comparison Mode; used only for this bounded calculation and processed in memory without retention."
  },
  "weak": {
   "type": "boolean",
   "description": "Weak supplied to Etag Comparison Mode; used only for this bounded calculation and processed in memory without retention."
  },
  "right": {
   "type": "string",
   "maxLength": 8192,
   "description": "Right supplied to Etag Comparison Mode; used only for this bounded calculation and processed in memory without retention."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "matched": true,
   "left_weak": false,
   "comparison": "weak",
   "right_weak": true
  },
  "schema": "delx/util-etag-comparison-mode/v1",
  "status": "pass",
  "evidence": {
   "retained": false,
   "input_sha256": "43d7a0184e6bebe0515b0b8fc44fcb3a02fe3b3f6fd7bd1f08d1d525deeda0a5",
   "external_calls": 0
  },
  "operation": "web_reliability:etag_comparison_mode"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-commerce-etag-comparison-mode-5c95e5c5/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)