with-eval

with-eval is a skill for Claude Code, Codex from nicolasmelo1/logion. It costs 104 tokens per session (1,530 once invoked), scanned A, original, MIT.

A checklist-based reviewer for code changes, such as a pull request—the proposed change developers inspect before it is merged.

In plain words
What is it for?
Use it to check diffs for issues such as SQL injection, exposed secrets, unchecked input, missing error handling, resource leaks, and logic mistakes.
Why use it?
It reduces the chance of missing common security, reliability, and correctness problems during review.

Skill for Claude CodeCodex

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 skills/nicolasmelo1/logion/with-eval
Any agent
npx skills add nicolasmelo1/logion --skill with-eval
Clone the repo
git clone --depth 1 https://github.com/nicolasmelo1/logion

Made for: Claude Code, Codex.

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 with-eval

README.md
[![agentmods](https://agentmods.dev/badge/skills/nicolasmelo1/logion/with-eval.svg)](https://agentmods.dev/skills/nicolasmelo1/logion/with-eval)
Your own site
<a href="https://agentmods.dev/skills/nicolasmelo1/logion/with-eval"><img src="https://agentmods.dev/badge/skills/nicolasmelo1/logion/with-eval.svg" alt="Measured on agentmods" height="20"></a>
Per session 104 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,530 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 $0.00104 $0.01530
Opus 5 $0.00052 $0.00765
Sonnet 5 $0.00021 $0.00306
Haiku 4.5 $0.00010 $0.00153

Measured 4d ago against content hash ce5fa599aaba, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

with-eval 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 4d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (evals/runner.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

examples/courses/with-eval/SKILL.md · 131 lines

How it starts

The opening of the file, as written. The whole thing — 131 lines — stays where its author put it; the contents beside it link to each section on GitHub.

With-Eval: Checklist-Driven PR Review

This skill reviews code diffs against a bundled checklist. The agent reads references/checklist.md, walks the diff category by category, and writes a structured review naming any violated categories by their stable code (e.g. security:sql-injection, reliability:missing-error-handling).

The output format is deliberately structured — one line per finding, with the category code, file path, line number, and a short description. The categories don't change between versions, so reviews are comparable across diffs and across time.

How the agent uses this skill

When asked to review a diff:

  1. Read references/checklist.md (loaded on-demand via progressive disclosure — not loaded at activation).
  2. Walk the diff against each category in the checklist.
  3. For each issue found, write one line in the format:
    <category-code> <path>:<line> — <short description>
    
  4. If the diff is clean, write a single line: no issues.

That's the entire workflow. The user gets a list of categorised findings or a clean bill of health.

Example output

For a diff that introduces a string-concatenated SQL query and a hardcoded API key:

security:sql-injection users/dao.py:7 — query built via string concatenation with user-supplied `email`
security:hardcoded-secret users/dao.py:4 — API key stored as a string literal

When to use this skill

  • Pre-merge PR review (the obvious case).
  • Auditing a vendor patch before applying it.
  • Self-review before pushing a feature branch.
  • Anywhere you'd otherwise get a free-form "looks good 👍" from an agent — this skill forces a categorised answer.

Capability declarations

  • tools: [file, terminal] — reads the diff, the checklist, writes the review.
  • filesystem.write: [./evals/reviews, ./evals/reports] — review output + self-test verdicts (see below).
  • No network, no secrets, no human approval. The skill runs entirely locally.

Verifying the skill works: bundled self-test

Read the full file on GitHub · 131 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. 4d ago First seen · 131 lines · 104 tokens per session scan A ce5fa599aaba

Subscribe to this mod's changes

with-eval is a skill published in the GitHub repository nicolasmelo1/logion (36 stars, last pushed today), licensed MIT. It adds 104 tokens to every session and 1,530 once invoked, about $0.0005 per session on Opus 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 2026-08-30.