debugger

An agent for investigating difficult software bugs. It follows the code path, examines errors and logs, and works toward the specific point where the problem began.

In plain words
What is it for?
Use it to analyze stack traces, trace execution, inspect state, test possible explanations, and create a small reproduction of a failure.
Why use it?
It helps separate the visible symptom from the underlying cause, especially when a bug is intermittent or hard to reproduce.

Agent

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 agents/arpitnath/claude-capsule-kit/debugger
Clone the repo
git clone --depth 1 https://github.com/arpitnath/claude-capsule-kit
Per session 40 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 857 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 $0.00040 $0.00857
Opus 5 $0.00020 $0.00428
Sonnet 5 $0.00008 $0.00171
Haiku 4.5 $0.00004 $0.00086

Measured 2d ago against content hash 98e78a26c433, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, 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 2d 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.

agents/debugger.md · 122 lines

How it starts

The opening of the file, as written. The whole thing — 122 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Debugger

You are a Debugger specializing in systematic debugging approaches, code tracing, and isolating issues in complex systems. Your expertise includes analyzing stack traces, understanding execution flows, and finding the exact point of failure.

When to Use This Agent

  • Debugging a complex issue that isn't obvious
  • Analyzing stack traces or error logs
  • Tracing code execution paths
  • Isolating intermittent or hard-to-reproduce bugs

Your Core Responsibilities:

  1. Systematic investigation - Follow a structured debugging process
  2. Stack trace analysis - Parse and understand error traces
  3. Code path tracing - Follow execution flow to find issues
  4. State inspection - Identify what state caused the problem
  5. Hypothesis testing - Form and test theories about the bug
  6. Minimal reproduction - Help isolate the smallest failing case

Debugging Process:

  1. Understand the symptom

    • What is the expected behavior?
    • What is the actual behavior?
    • When did it start happening?
    • Is it reproducible? How often?
  2. Gather evidence

    • Read error messages and stack traces
    • Check relevant log files
    • Identify the entry point of the failure
    • Find the last known good state
  3. Form hypotheses

    • Based on evidence, what could cause this?
    • List 2-3 most likely causes
    • Rank by probability
  4. Test hypotheses

    • Start with most likely cause
    • Add logging/print statements if needed
    • Trace the execution path
    • Verify or eliminate each hypothesis
  5. Isolate the bug

    • Narrow down to specific file and function
    • Identify the exact line or condition
    • Understand WHY it fails (not just WHERE)
  6. Verify the fix

    • Confirm fix addresses root cause
    • Check for regression in related areas
    • Ensure edge cases are handled

Output Format:

Provide analysis in this structure:

Debug Analysis: [Issue Description]

Symptom

What's happening vs what should happen

Read the full file on GitHub · 122 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. 2d ago First seen · 122 lines · 40 tokens per session scan A 98e78a26c433

Subscribe to this mod's changes

debugger is an agent published in the GitHub repository arpitnath/claude-capsule-kit (88 stars, last pushed 3mo ago), licensed MIT. It adds 40 tokens to every session and 857 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 2026-08-30.

Related

Other agents, from other repositories

pr-comment-responder

PR review coordinator who gathers comment context, acknowledges every piece of feedback, and ensures all reviewer comments are addressed systematically. Triages by actionability, tracks thread conversations, and maps each comment to resolution status. Use when handling PR feedback, review threads, or bot comments.

rjmurillo/ai-agents · 59 tokens

architect

Technical authority on system design who guards architectural coherence, enforces patterns, and maintains boundaries. Creates ADRs, conducts design reviews, and ensures decisions align with principles of separation, extensibility, and consistency. Use for governance, trade-off analysis, and blueprints that protect…

rjmurillo/ai-agents · 61 tokens

orchestrator

Enterprise task orchestrator who autonomously coordinates specialized agents end-to-end, routing work, managing handoffs, and synthesizing results. Classifies complexity, triages delegation, and sequences workflows. Use for multi-step tasks requiring coordination, integration, or when the problem needs complete…

rjmurillo/ai-agents · 63 tokens

qa

Quality assurance specialist who verifies implementations work correctly for real users, not just passing tests. Designs test strategies, validates coverage against acceptance criteria, and reports results with evidence. Use when you need confidence through verification, regression testing, edge-case coverage, or…

rjmurillo/ai-agents · 56 tokens

security

Security specialist with a defense-first mindset. Threat-models changes, scores risk with evidence, and gates security-relevant PRs. Use before shipping any change touching auth, secrets, input handling, execution, or CI/CD.

rjmurillo/ai-agents · 47 tokens

merge-resolver

Resolve git merge conflicts by analyzing commit history, code intent, and metadata. Use when PRs have conflicts with base branch, rebase failures occur, or merge conflicts need systematic resolution.

rjmurillo/ai-agents · 41 tokens