eval-compare

A command for comparing two saved versions of a skill. A version can be a file or a named snapshot stored by the local evaluator.

In plain words
What is it for?
Resolving version files or snapshots, checking cached evaluation results, and comparing the quality results of two skill versions.
Why use it?
It makes changes between skill versions visible and warns when the two versions belong to different skills, where comparison may be misleading.

Command

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.

agentmods
npx agentmods add commands/evol-ai/skillcompass/eval-compare
Clone the repo
git clone --depth 1 https://github.com/Evol-ai/SkillCompass
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 753 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00000 $0.00753
Opus 5 $0.00000 $0.00377
Sonnet 5 $0.00000 $0.00151
Haiku 4.5 $0.00000 $0.00075

Measured 2d ago against content hash ffe4f93f44d6, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

eval-compare 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 2d ago.

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.

commands/eval-compare.md · 80 lines

How it starts

The opening of the file, as written. The whole thing — 80 lines — stays where its author put it; the contents beside it link to each section on GitHub.

/eval-compare — Version Comparison

Locale: All templates in this spec are written in English. Detect the user's language from the session and translate user-facing text at display time per SKILL.md's Global UX Rules. Dimension labels: see the canonical table in SKILL.md.

Arguments

  • <version-a> (required): File path or {skill-name}@{version} identifier.
  • <version-b> (required): File path or {skill-name}@{version} identifier.
  • --internal / --ci (optional): Skip interactive choice prompts; output results and exit.

Steps

Step 1: Resolve Versions

For each argument:

  • If it's a file path: use the Read tool to load the file directly.
  • If it's a name@version identifier: look up .skill-compass/{name}/snapshots/{version}.md using the Read tool.
  • If version not found: output "Version not found: {identifier}" and stop.

Cross-skill check: If both arguments use name@version syntax and the skill names differ, warn the user that they are comparing different skills ({name_a} vs {name_b}) and the result may lack meaningful reference value, then present the choice:

[Continue comparing / Cancel]

If the user chooses Cancel, stop.

Step 2: Check Cached Results

For each version, check .skill-compass/{name}/manifest.json for cached evaluation results. Use the Read tool to load the manifest.

If cached results exist (matching content_hash): use cached scores. If not: run eval-skill flow on the version to generate fresh results.

Step 3: Compare

Generate a side-by-side comparison:

Version Comparison: sql-optimizer
| Dimension       | v1.0.0 | v1.0.0-evo.2 | Delta  |
|-----------------|--------|--------------|--------|
| D1 Structure    |      6 |            7 | ↑ +1   |
| D2 Trigger      |      3 |            6 | ↑ +3 * |
| D3 Security     |      2 |            7 | ↑ +5 * |
| D4 Functional   |      4 |            4 | → 0    |
| D5 Comparative  |      3 |            3 | → 0    |
| D6 Uniqueness   |      7 |            7 | → 0    |
|-----------------|--------|--------------|--------|
| Overall         |     38 |           52 | ↑ +14  |
| Verdict         |   FAIL |      CAUTION |        |

Read the full file on GitHub · 80 lines

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. 2d ago First seen · 80 lines · 0 tokens per session scan A ffe4f93f44d6

Subscribe to this mod's changes

eval-compare is a command published in the GitHub repository Evol-ai/SkillCompass (215 stars, last pushed 4mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 753 tokens. 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 2026-08-30.