logic-lens

logic-lens is a skill for Claude Code from skillmds/skillmd. It costs 37 tokens per session (1,154 once invoked), scanned A, original, MIT.

An in-depth code-review method that reasons about how a program behaves, rather than checking only syntax or style.

In plain words
What is it for?
It is for reviewing complex or security-sensitive code, investigating hard-to-find bugs, checking refactors, and assessing logic before a pull request is merged.
Why use it?
It can expose problems that simple linters often miss, including race conditions, incorrect state changes, boundary errors, and flawed algorithms.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: mentions Claude Code; mentions Codex.

Part of the code-security-review-pipeline plugin — 15 skills shipped together

Good fit It is for reviewing complex or security-sensitive code, investigating hard-to-find bugs, checking refactors, and assessing logic before a pull request is merged.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/skillmds/skillmd/logic-lens
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 skillmds/skillmd --skill logic-lens
Clone the repo
git clone --depth 1 https://github.com/skillmds/skillmd

Made for: Claude Code.

Or install code-security-review-pipeline, the plugin that ships this one along with the rest of its 15 skills.

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 logic-lens

README.md
[![agentmods](https://agentmods.dev/badge/skills/skillmds/skillmd/logic-lens/github.svg)](https://agentmods.dev/skills/skillmds/skillmd/logic-lens)
Your own site
<a href="https://agentmods.dev/skills/skillmds/skillmd/logic-lens"><img src="https://agentmods.dev/badge/skills/skillmds/skillmd/logic-lens/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 logic-lens

Your own site · 80×15
<a href="https://agentmods.dev/skills/skillmds/skillmd/logic-lens"><img src="https://agentmods.dev/badge/skills/skillmds/skillmd/logic-lens.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 37 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,154 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 $0.00037 $0.01154
Opus 5.5 $0.00015 $0.00462
Sonnet 5 $0.00007 $0.00231
Haiku 4.5 $0.00004 $0.00115

Measured 4d ago against content hash fc2846eac595, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-23, from the pricing page.

Security

Grade A, and why

logic-lens 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.

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.

plugins/code-security-review-pipeline/skills/logic-lens/SKILL.md · 127 lines

How it starts

The opening of the file, as written. The whole thing — 127 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Logic Lens

Overview

Logic Lens is a Claude Code skill that performs deep, logic-driven code review using formal reasoning frameworks. Unlike traditional linters that check syntax and style, Logic Lens analyzes your code for logical errors, race conditions, security vulnerabilities, type mismatches, and algorithmic flaws that only appear when you reason through the code's behavior.

Powered by structured AI analysis, Logic Lens applies systematic logical inspection across 9 risk categories: null/undefined handling, type safety, concurrency, resource management, security injection, boundary conditions, algorithm correctness, state management, and API contract violations.

When to Use This Skill

  • Use when you want a thorough logic review before merging a PR
  • Use when a bug seems hard to find and standard linters aren't helping
  • Use when reviewing security-sensitive code paths (auth, payments, file access)
  • Use when refactoring complex business logic
  • Use when onboarding to a new codebase and need to understand risk areas

How It Works

Logic Lens uses Claude Code's reasoning capabilities to:

  1. Parse code structure and build a mental model of data flow
  2. Apply formal logic checks across 9 risk categories
  3. Trace execution paths for edge cases and boundary conditions
  4. Identify security anti-patterns (injection, privilege escalation, data leakage)
  5. Report findings with severity levels and actionable fix suggestions

Installation

# Install via Claude Code plugin marketplace
# Search: "logic-lens" in Claude Code > Extensions

# Or install via NPX (Antigravity)
npx antigravity-awesome-skills --claude
# Then invoke: @logic-lens

Examples

Example 1: Review a Single File

@logic-lens review src/auth/login.ts for security issues

Logic Lens output:

[CRITICAL] SQL Injection risk at line 42: user input concatenated into query string
[HIGH] Missing rate limiting on login attempts
[MEDIUM] Password comparison uses == instead of timing-safe comparison
[LOW] Error messages may leak valid usernames (user enumeration)

Read the full file on GitHub · 127 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 · 127 lines · 37 tokens per session scan A fc2846eac595

Subscribe to this mod's changes

logic-lens is a skill published in the GitHub repository skillmds/skillmd (1 stars, last pushed yesterday), licensed MIT. It adds 37 tokens to every session and 1,154 once invoked, about $0.0001 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 2026-09-19.

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