Rubric Signal Plugin Tutorial

Purpose

Learn how LenserFight scoring plugins turn submission text into deterministic numeric signals.

Concepts Covered

Scoring, scoring plugin, SubmissionView, ScoringResult, result aggregation, failure handling.

What You Will Build

You will run examples/scoring/rubric-signal-plugin, a local plugin-shaped module with id, metadata, and score.

Prerequisites

• Node 22.

File Structure

examples/scoring/rubric-signal-plugin/
  src/
    index.mjs
    demo.mjs
  README.md

Step-by-Step Walkthrough

1. Open src/index.mjs.
2. Inspect REQUIRED_TERMS.
3. Inspect the score(submission) method.
4. Notice the empty-content failure result.
5. Run the demo.

How to Run the Example

node examples/scoring/rubric-signal-plugin/src/demo.mjs

Expected Output

The script prints plugin metadata and an ok: true result similar to:

signals: { word_count: 18, required_term_hits: 3, rubric_hit_ratio: 1 }

Exact word count may change if you edit the demo submission.

How the Example Works Internally

The plugin treats the submission as a pure input value. It counts words, checks required rubric terms, and returns numeric signals. It performs no network or database calls.

Common Errors and Troubleshooting

• ok: false: the submission text is empty or null.
• A high signal is not a final verdict; it is a scoring input that still needs interpretation.
• Keep signals numeric so they can be aggregated consistently.

Suggested Modifications

• Add a max_word_count signal.
• Make required terms configurable in a factory option.
• Add a demo for a failed empty submission.

Example Folder

examples/scoring/rubric-signal-plugin