debugger

debugger is an agent for Claude Code from dotclaude/marketplace. It costs 23 tokens per session (157 once invoked), scanned A, a copy of debugging-toolkit-debugger, MIT.

A specialist for finding the underlying cause of errors, failed tests, and unexpected program behavior.

In plain words
What is it for?
Use it to analyze error messages and logs, inspect recent changes and variable states, add debug logging, and plan prevention tests.
Why use it?
It provides a structured way to reproduce a problem, isolate its source, apply a small fix, and check that the fix works.

Agent for Claude Code

Written for Claude Code: a Claude Code subagent (agents/*.md). Also seen: model in frontmatter.

Good fit Use it to analyze error messages and logs, inspect recent changes and variable states, add debug logging, and plan prevention tests.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/dotclaude/marketplace/debugger
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/dotclaude/marketplace

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 debugger

README.md
[![agentmods](https://agentmods.dev/badge/agents/dotclaude/marketplace/debugger/github.svg)](https://agentmods.dev/agents/dotclaude/marketplace/debugger)
Your own site
<a href="https://agentmods.dev/agents/dotclaude/marketplace/debugger"><img src="https://agentmods.dev/badge/agents/dotclaude/marketplace/debugger/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 debugger

Your own site · 80×15
<a href="https://agentmods.dev/agents/dotclaude/marketplace/debugger"><img src="https://agentmods.dev/badge/agents/dotclaude/marketplace/debugger.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 23 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 157 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 94% copy Near-identical to another mod 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 $0.00023 $0.00157
Opus 5.5 $0.00009 $0.00063
Sonnet 5.5 $0.00005 $0.00031
Haiku 4.5 $0.00002 $0.00016

Measured 1mo ago against content hash 15163e355ebc, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

debugger 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 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.

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.

Origin

This is a copy

94% identical to debugging-toolkit-debugger — 5 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

plugins/dev-accelerator/agents/debugger.md · 31 lines

What it actually says

You are an expert debugger specializing in root cause analysis.

When invoked:

  1. Capture error message and stack trace
  2. Identify reproduction steps
  3. Isolate the failure location
  4. Implement minimal fix
  5. Verify solution works

Debugging process:

  • Analyze error messages and logs
  • Check recent code changes
  • Form and test hypotheses
  • Add strategic debug logging
  • Inspect variable states

For each issue, provide:

  • Root cause explanation
  • Evidence supporting the diagnosis
  • Specific code fix
  • Testing approach
  • Prevention recommendations

Focus on fixing the underlying issue, not just symptoms.

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 · 31 lines · 23 tokens per session scan A 15163e355ebc

Subscribe to this mod's changes

debugger is an agent published in the GitHub repository dotclaude/marketplace (43 stars, last pushed 6mo ago), licensed MIT. It adds 23 tokens to every session and 157 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 94% identical to debugging-toolkit-debugger, differing in 5 lines, and is treated as a copy.

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