eval-rubric

eval-rubric is a skill for Claude Code, Codex from Calibre-Labs/reforge-ai-evals. It costs 148 tokens per session (2,156 once invoked), scanned A, original, MIT.

A writing tool for an evaluation rubric, which is a list of pass-or-fail checks defining good behavior for an AI product or agent. It covers the result, the steps taken, governance, and user experience, with release limits kept separate.

In plain words
What is it for?
Use it to write a first rubric from a product description, update one after reviewing traces, or audit an existing rubric.
Why use it?
It gives teams a shared definition of quality before or after they inspect agent runs. This makes evaluation less dependent on vague opinions and helps connect findings to product requirements.

Skill for Claude CodeCodex

Written for Claude Code and Codex: shipped in a Claude Code plugin, but also agents/openai.yaml present.

Part of the ai-evals plugin — 8 skills, 8 commands shipped together

Good fit Use it to write a first rubric from a product description, update one after reviewing traces, or audit an existing rubric.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/calibre-labs/reforge-ai-evals/eval-rubric
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add Calibre-Labs/reforge-ai-evals --skill eval-rubric
Clone the repo
git clone --depth 1 https://github.com/Calibre-Labs/reforge-ai-evals

Made for: Claude Code, Codex.

Or install ai-evals, the plugin that ships this one along with the rest of its 8 skills, 8 commands.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for eval-rubric

README.md
[![agentmods](https://agentmods.dev/badge/skills/calibre-labs/reforge-ai-evals/eval-rubric/github.svg)](https://agentmods.dev/skills/calibre-labs/reforge-ai-evals/eval-rubric)
Your own site
<a href="https://agentmods.dev/skills/calibre-labs/reforge-ai-evals/eval-rubric"><img src="https://agentmods.dev/badge/skills/calibre-labs/reforge-ai-evals/eval-rubric/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for eval-rubric

Your own site · 80×15
<a href="https://agentmods.dev/skills/calibre-labs/reforge-ai-evals/eval-rubric"><img src="https://agentmods.dev/badge/skills/calibre-labs/reforge-ai-evals/eval-rubric.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 148 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,156 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00148 $0.02156
Opus 5.5 $0.00059 $0.00862
Sonnet 5.5 $0.00030 $0.00431
Haiku 4.5 $0.00015 $0.00216

Measured yesterday against content hash ef0dfa31b827, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

eval-rubric scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/eval-rubric/SKILL.md · 183 lines

How it starts

The opening of the file, as written. The whole thing — 183 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Eval rubric skill

An eval rubric is the written definition of good behavior for one AI product. It is a section of the PRD. Every line is a pass/fail check on a single trace. Numbers that hold across many traces (cost, latency, failure rate) are release thresholds and live in their own PRD section.

This skill writes v1 before any traces exist, and v2 after traces have been read. It also audits a rubric someone else wrote.

Read references/worked-examples.md before writing a rubric for the first time in a session. It shows two products taken from v1 to v2.

Pick the mode

The user has Mode
A PRD, spec, system prompt or a product description, and no traces yet v1
A v1 rubric plus trace codes or annotated traces v2
A rubric and wants feedback on it Audit

If it is unclear, ask one question: "Have you read traces from this agent yet?"

The four kinds of lines

Group Question it answers Comes from Typical owner
Outcome (O) What did it produce, and is it right? Definition of success PM, subject expert, engineering
Trajectory (T) How did it get there? Autonomy table, known risks Engineering
Governance (G) What must it never do, and always do? Tool surface, policy, non-goals Legal, finance, security
Experience (X) How did it feel to the user in this channel? User and channel Design

Rules for every line:

  • One behavior per line. If a line has "and" joining two behaviors, split it.
  • Pass or fail on one trace. A reviewer reading a single session can decide.
  • Observable. The evidence is in the trace: an output, a tool call, an argument, a message.
  • About the product, not one demo task. A line written for a coffee order should also hold for the pharmacy pickup. If it mentions the demo's subject, rewrite it.
  • Specific to this product. Generic lines such as "is helpful" or "is safe" are not rubric lines.
  • Governance lines start with "Never" or "Always".
  • Give each line an ID: O1, O2, T1, G1, X1. IDs are stable across versions.

Read the full file on GitHub · 183 lines

Files

What ships with it

4 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 183 lines · 148 tokens per session scan A ef0dfa31b827

Subscribe to this mod's changes

eval-rubric is a skill published in the GitHub repository Calibre-Labs/reforge-ai-evals (75 stars, last pushed yesterday), licensed MIT. It adds 148 tokens to every session and 2,156 once invoked, about $0.0006 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-10-17.