bug-fixer

bug-fixer is an agent for Claude Code from PacktPublishing/The-Claude-Code-Operating-Model. It costs 28 tokens per session (226 once invoked), scanned B, original, MIT.

A code-editing agent that applies a small, targeted fix based on a bug-location report.

In plain words
What is it for?
Use it after a bug has been located to update the relevant file, explain the change, and avoid unrelated refactoring.
Why use it?
It changes only the affected code and leaves test execution to a separate verification step.

Agent for Claude Code

Written for Claude Code: installed under .claude/.

Good fit Use it after a bug has been located to update the relevant file, explain the change, and avoid unrelated refactoring.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/packtpublishing/the-claude-code-operating-model/bug-fixer
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.

Clone the repo
git clone --depth 1 https://github.com/PacktPublishing/The-Claude-Code-Operating-Model

Made for: Claude Code.

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-fixer

README.md
[![agentmods](https://agentmods.dev/badge/agents/packtpublishing/the-claude-code-operating-model/bug-fixer/github.svg)](https://agentmods.dev/agents/packtpublishing/the-claude-code-operating-model/bug-fixer)
Your own site
<a href="https://agentmods.dev/agents/packtpublishing/the-claude-code-operating-model/bug-fixer"><img src="https://agentmods.dev/badge/agents/packtpublishing/the-claude-code-operating-model/bug-fixer/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 bug-fixer

Your own site · 80×15
<a href="https://agentmods.dev/agents/packtpublishing/the-claude-code-operating-model/bug-fixer"><img src="https://agentmods.dev/badge/agents/packtpublishing/the-claude-code-operating-model/bug-fixer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 28 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 226 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 1 finding. 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 $0.00028 $0.00226
Opus 5.5 $0.00011 $0.00090
Sonnet 5.5 $0.00006 $0.00045
Haiku 4.5 $0.00003 $0.00023

Measured 1mo ago against content hash 3a5e5ca702b8, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade B, and why

bug-fixer scanned grade B with 1 finding 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 1mo 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.

Unrestricted tool accessmediumExcessive agency

A wildcard tool grant or "run any command" leaves no least-privilege boundary at all.

- Do NOT execute any commands
Origin

Copies of this mod

1 near-identical copy found in the catalogue:

  • bug-fixer — 100% identical, 0 lines differ
ch04-subagents/.claude/agents/bug-fixer.md · 34 lines

What it actually says

Bug Fixer Agent

You are a bug fixer specialist. You receive a bug location report and apply the minimal fix.

Process

  1. Read the bug locator's report
  2. Read the affected file to understand full context
  3. Apply the minimal fix — change as few lines as possible
  4. Verify your fix doesn't break the surrounding logic

Output Format

## Fix Applied
- **File**: [file path]
- **Change**: [what was changed]
- **Before**: [old code]
- **After**: [new code]
- **Reasoning**: [why this fix is correct]

Rules

  • Apply the MINIMAL fix — don't refactor surrounding code
  • Do NOT run tests (that's the verifier's job)
  • Do NOT execute any commands
  • If the bug report is unclear, report back — don't guess
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. 1mo ago First seen · 34 lines · 28 tokens per session scan B 3a5e5ca702b8

Subscribe to this mod's changes

bug-fixer is an agent published in the GitHub repository PacktPublishing/The-Claude-Code-Operating-Model (18 stars, last pushed 2mo ago), licensed MIT. It adds 28 tokens to every session and 226 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it B with 1 finding (unrestricted tool access). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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