# Delx Set Diff

> Delx Set Diff 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).

Computes the set difference (a minus b), returning elements in array a that are not present in array b, along with a count.

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/set-diff
- 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/delx-set-diff-2b5c8ddc
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_cONgRvIvl_WnrydLrcALI

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-set-diff-2b5c8ddc -d '<json body>'
```

Example prompt: I have a candidate list [101, 202, 303, 404, 505] and a blocklist [202, 404] — remove the blocked IDs from the candidates and tell me what's left.

## When to prefer this

Choose this endpoint when you need a fast, cheap, stateless set-difference computation without standing up any infrastructure — ideal for agent workflows that need to subtract blocklists, deny lists, or already-processed IDs from candidate arrays in real time. It is purpose-built for agentic use: no API keys, no data retention, and payment via x402 on Base at $0.001 USDC per call.

## Known failure modes

- Missing or malformed array a or b returns a validation error
- Non-array inputs cause a schema rejection
- Payment failure via x402 on Base prevents the call from executing
- Duplicate elements within a or b may affect result depending on implementation
- Empty array a always returns an empty difference with count zero

## How this service works

Set difference a - b. Call when you remove blocked IDs from agent candidate lists. Returns difference items and count for $0.001 USDC via x402 on Base. No network, no keys, no retention; first-party local JSON only. Results are advisory; the caller owns budgets, auth, and production controls.

## Output

Returns the set difference — an array of elements that appear in array a but not in array b — along with a count of those items. No data is retained server-side; results are computed locally on the fly.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "a": {
   "type": "array",
   "description": "Input field: a."
  },
  "b": {
   "type": "array",
   "description": "Input field: b."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "count": 2,
  "items": [
   1,
   3
  ],
  "schema": "delx/util-set-diff/v1"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-set-diff-2b5c8ddc/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)