bug-fix

bug-fix is a skill for Claude Code from LeekJay/claude-skills-plugin. It costs 45 tokens per session (4,531 once invoked), scanned A, original, MIT.

A bug-fixing workflow for finding the cause of software problems and applying a verified fix. It handles small issues directly and can pass complex bugs involving several files to a separate coding agent.

In plain words
What is it for?
Investigating errors and stack traces, tracing unexpected behavior, fixing logic or type mistakes, resolving multi-file bugs, and addressing regressions, race conditions, memory leaks, or data inconsistencies.
Why use it?
It helps distinguish the underlying cause from visible symptoms and includes checks to reduce the chance of introducing another problem.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter. Also seen: mentions subagents.

Part of the bug-fix plugin — 1 skill, 1 agent shipped together

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/leekjay/claude-skills-plugin/bug-fix
Any agent
npx skills add LeekJay/claude-skills-plugin --skill bug-fix
Clone the repo
git clone --depth 1 https://github.com/LeekJay/claude-skills-plugin

Made for: Claude Code.

Or install bug-fix, the plugin that ships this one along with the rest of its 1 skill, 1 agent.

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 bug-fix

README.md
[![agentmods](https://agentmods.dev/badge/skills/leekjay/claude-skills-plugin/bug-fix.svg)](https://agentmods.dev/skills/leekjay/claude-skills-plugin/bug-fix)
Your own site
<a href="https://agentmods.dev/skills/leekjay/claude-skills-plugin/bug-fix"><img src="https://agentmods.dev/badge/skills/leekjay/claude-skills-plugin/bug-fix.svg" alt="Measured on agentmods" height="20"></a>
Per session 45 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,531 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 5.1 $0.00045 $0.04531
Opus 5 $0.00023 $0.02266
Sonnet 5 $0.00009 $0.00906
Haiku 4.5 $0.00005 $0.00453

Measured 5d ago against content hash 021efd9fcc8e, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

bug-fix 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 5d 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/bug-fix/skills/bug-fix/SKILL.md · 763 lines

How it starts

The opening of the file, as written. The whole thing — 763 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Bug Fix Skill

Overview

This skill provides intelligent bug fixing capabilities through a hybrid architecture:

  • Skill mode: Direct handling in main conversation for simple, isolated bugs
  • Sub-agent mode: Delegate complex, multi-file bugs to isolated executor context

When to Use This Skill

✅ Use This Skill For:

Bug Identification & Analysis:

  • Diagnosing runtime errors and exceptions
  • Analyzing stack traces and error messages
  • Identifying root causes of unexpected behavior
  • Tracing bugs through call chains

Simple Bug Fixes:

  • Single-file bug fixes
  • Logic errors in specific functions
  • Off-by-one errors and boundary conditions
  • Type errors and null/undefined issues
  • Simple state management bugs

Complex Bug Fixes:

  • Bugs spanning multiple files
  • Race conditions and concurrency issues
  • Memory leaks and performance bugs
  • Integration bugs across modules
  • Data consistency issues

Regression Fixes:

  • Bugs introduced by recent changes
  • Breaking test cases
  • API contract violations
  • Behavior changes affecting downstream code

❌ Don't Use For:

  • Feature requests (not bugs)
  • Code refactoring (unless fixing a bug)
  • Performance optimization (unless it's a performance bug)
  • Code style improvements
  • Adding new functionality

Decision Framework

Default behavior: For bug fixing tasks, prefer Sub-Agent mode unless the task is clearly simple.

🔴 Mandatory Sub-Agent Triggers (ANY ONE triggers delegation)

  1. Multi-file scope: Bug description mentions 2+ files or modules
  2. Unknown root cause: Requires investigation ("sometimes...", "occasionally...", "intermittent...")
  3. Complex keywords: Description contains race condition, memory leak, data inconsistency, state sync, cache issues, deadlock
  4. Cross-layer issues: Involves frontend+backend, multiple services, database+application layer
  5. Debugging required: Needs logging, breakpoints, execution flow tracing
  6. Regression/recurring: Bug existed before, was fixed but reappeared, or has history
  7. Test-related: Needs test writing for verification, involves test framework issues
  8. Unclear reproduction: User cannot reliably reproduce the bug

Read the full file on GitHub · 763 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. 5d ago First seen · 763 lines · 45 tokens per session scan A 021efd9fcc8e

Subscribe to this mod's changes

bug-fix is a skill published in the GitHub repository LeekJay/claude-skills-plugin (4 stars, last pushed 8mo ago), licensed MIT. It adds 45 tokens to every session and 4,531 once invoked, about $0.0002 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 2026-08-31.

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