# AISkills402: Spend Cap Review

> AISkills402: Spend Cap Review is a paid API for AI agents from api.aiskills402.com, paid per call via x402, $0.03/call, status unknown (last checked 2026-10-14).

Reviews pasted code and configuration to verify whether spending limits (for paid AI, API calls, or billed usage) actually block spending, or merely sit beside the execution path.

## Facts

- Endpoint: GET https://api.aiskills402.com/v1/skills/spend-guard-review/file?utm_source=zero.xyz
- Price: $0.03/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/aiskills402-spend-cap-review-fe9d6246
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_QRVdvIJoDkHQ28JQ-5oS_

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 aiskills402-spend-cap-review-fe9d6246
```

Example prompt: Can you review this code and config and tell me whether my $50/month OpenAI spend cap will actually stop API calls from going through, or if it's just sitting beside the execution path without blocking anything?

## When to prefer this

Choose this endpoint when you need a semantic, reasoning-based audit of whether a cost cap is architecturally effective — not just syntactically present. It is distinct from linters or static analysis tools because it reasons about execution paths, provider call routing, and whether the limiting control is actually interposed between the spender and the billing event. Best for code + config reviews involving paid AI APIs, cloud billing controls, or per-use billed services.

## Known failure modes

- No code or configuration provided — review cannot proceed without paste-able input
- Input too large or malformed — request rejected or truncated analysis
- Payment not settled — x402 payment required at $0.03 USDC before file is delivered
- Network timeout — retry with backoff
- SHA256 mismatch on returned file — redownload via the provided redownload URL

## How this service works

Spend Cap Review: Do Cost Limits Really Stop? — Reviews pasted code and configuration that spends money (paid AI or API calls, purchases, paid lookups, anything billed per use) and checks whether the limit on that spending really stands in the way of the spending. It flags a cap that sits beside the path instead of on it (a gateway limit while a script calls the provider directly, a counter only in the browser), a missing setting that means no limit, an alert or a budget email used as the prote…

## Output

A SKILL.md file containing a structured spend-cap review: flagged issues where cost limits sit beside rather than on the execution path, missing cap settings, alerts or emails used as the sole control, browser-only counters, and any configuration gaps that would allow spending to continue past the stated limit. Returned with a redownload token and settlement receipt.

## 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"
     ],
     "type": "string"
    },
    "headers": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "file": {
   "name": "SKILL.md",
   "content": "<the SKILL.md file>",
   "encoding": "utf-8"
  },
  "name": "Spend Cap Review: Do Cost Limits Really Stop?",
  "skill": "spend-guard-review",
  "sha256": "<sha256 of SKILL.md>",
  "receipt": {
   "tx": "0x<settlement transaction>",
   "settled": true
  },
  "version": "1.0.0",
  "redownload": {
   "url": "<api>/v1/purchases/<token>",
   "token": "<64 hex chars>"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/aiskills402-spend-cap-review-fe9d6246/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.aiskills402.com](https://www.zero.xyz/host/api.aiskills402.com/llms.txt)