# The six mechanically checkable criterion types

Deterministic, no AI judging. Each example below is one criterion you can paste into `criteria`.

1. `evidence_present` — the item exists and is non-empty. A missing key, `null`, an empty array and a whitespace-only string all fail.

    {"type":"evidence_present","key":"test_log"}

2. `hash_matches` — sha256 of the value's UTF-8 bytes equals the declared digest. A string value is hashed as-is, matching `sha256sum <file>`; a non-string value is hashed as its compact `JSON.stringify` output.

    {"type":"hash_matches","path":"changelog","sha256":"3bfc269594ef649228e9a74bab00f042efc91d5acc6fbee31a382e80d42388fe"}

3. `url_status` — the URL returns the expected integer status code.

    {"type":"url_status","url":"https://example.com","expect":200}

4. `url_contains` — the fetched content contains the string (case-sensitive).

    {"type":"url_contains","url":"https://example.com","contains":"Example"}

5. `json_path` — a dotted path into `evidence` exists; with `equals`, the two are compared by string form, so `9` matches `"9"`.

    {"type":"json_path","path":"test_summary.total","equals":9}

6. `count_min` — an array's length, an object's key count, or the number itself is at least `min`.

    {"type":"count_min","path":"boundary_cases","min":3}

`key` and `path` both accept dotted paths (`a.b.c`). Both URL types also accept `render: true`. When a key is missing, `missing` names the top-level evidence keys you actually sent, so one retry is usually enough.

中文：六种可机械核对类型——存在性、sha256 一致性、URL 状态码、URL 内容包含、JSON 路径、数量下限；字段名照抄，`key`/`path` 支持 `a.b` 点号路径，URL 两类可选 `render:true`。键名写错时 `missing` 会列出你实际给的 evidence 顶层键。

## Source

https://nodcheck.com/answers/six-check-types