Moderation

The POST /v1/moderations endpoint is an OpenAI-compatible content moderation mock. Register fixture patterns on the LLMock instance and the request input is matched against them — first match wins, no match returns a default unflagged result.

Endpoint

How It Works

• The input field is matched against registered patterns — string patterns are case-insensitive substring matches, RegExp patterns are tested as-is
• First matching fixture wins, so register specific patterns before catch-alls
• Unmatched inputs return a default result with flagged: false and every category (and category score) set to false / 0
• Under strict mode (--strict, or X-AIMock-Strict: true on the request), an unmatched input returns 503 no_fixture_match instead of the unflagged default
• An array input is joined with spaces for matching, and multimodal text parts contribute their text

Unit Test: Flagged Content

const mock = new LLMock();
mock.onModerate("violent", {
  flagged: true,
  categories: { violence: true, hate: false },
  category_scores: { violence: 0.95, hate: 0.01 },
});
await mock.start();

const res = await fetch(`${mock.url}/v1/moderations`, {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({ input: "a violent threat" }),
});

const body = await res.json();
expect(body.results[0].flagged).toBe(true);
expect(body.model).toBe("omni-moderation-latest");

Response Format

Matches the OpenAI /v1/moderations response format:

{
  "id": "modr-...",
  "model": "omni-moderation-latest",
  "results": [
    {
      "flagged": true,
      "categories": { "violence": true, "hate": false },
      "category_scores": { "violence": 0.95, "hate": 0.01 }
    }
  ]
}

Validation

• Malformed JSON bodies are rejected with 400
• An input that is neither a string, an array of strings, nor multimodal parts is rejected with 400
• A missing input matches against the empty string (usually a miss)

Journal Integration

Moderation requests are recorded in the LLMock journal with service: "moderation":

const entries = mock.getRequests();
const moderationRequests = entries.filter((e) => e.service === "moderation");