# AISkills402: Test Review — Can This Test Ever Fail?

> AISkills402: Test Review — Can This Test Ever Fail? is a paid API for AI agents from api.aiskills402.com, paid per call via x402, $0.03/call, status unknown (last checked 2026-10-18).

Analyzes a pasted test, check script, smoke test, mutation script, or CI step and determines whether it can actually fail when the guarded code is broken, exposing vacuous or incomplete tests.

## Facts

- Endpoint: GET https://api.aiskills402.com/v1/skills/test-guard-review/file?utm_source=zero.xyz
- Price: $0.03/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/aiskills402-test-review-can-this-test-ever-fail-b68ac887
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_RbI8WJglGKSnIDFUnNGur

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-test-review-can-this-test-ever-fail-b68ac887
```

Example prompt: Can you review this test script I wrote and tell me if it can actually fail when the code it's supposed to catch breaks — I want to know if a green result means anything or if it's just always green no matter what?

## When to prefer this

Choose this endpoint when you need expert-level analysis of whether a specific test, CI step, smoke test, or mutation script is genuinely capable of catching the defect it claims to guard — especially when you suspect the test may always pass regardless of code state. Prefer this over generic linting or static analysis tools when the concern is test validity and false confidence rather than syntax errors or style issues. It is particularly valuable for catching subtle failure modes like vacuous completeness guards, shallow glob patterns, null-passing assertions, and mutation scripts that destroy the very fix they are testing.

## Known failure modes

- Payment not settled — x402 payment required before content is returned
- Invalid or missing HTTP method — only GET and HEAD are accepted
- Network timeout if upstream skill processing is slow
- Script too large or malformed — may return error if input exceeds limits
- Empty or missing input body — returns error if no test content is provided

## How this service works

Test Review: Can This Test Ever Fail? — Reviews a pasted test, check script, smoke test, mutation script or CI step and says whether it can fail when the thing it guards is broken, so a green result is worth something. It finds a completeness guard that counts its own hard-coded list instead of the directory, a one-star glob that never enters subfolders, a mutation script that restores with git checkout and wipes the uncommitted fix under test, a null test that an empty string passes, a status …

## Output

Returns a SKILL.md file containing a structured expert review of the submitted test or script, including a verdict on whether the test can ever fail when the guarded system is broken, specific failure patterns detected (e.g. hardcoded counts, shallow globs, null-passing empty strings, self-destructing git restores), and an explanation of what makes each flaw dangerous. Also includes a SHA256 hash of the file, settlement receipt with transaction hash, and a redownload URL/token for future retrieval.

## 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": "Test Review: Can This Test Ever Fail?",
  "skill": "test-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-test-review-can-this-test-ever-fail-b68ac887/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)