debugger

debugger is an agent for Claude Code from webdevtodayjason/titanium-plugins. It costs 27 tokens per session (1,602 once invoked), scanned A, original, MIT.

An AI debugging specialist for finding the causes of errors, failed tests, and unexpected software behavior. It examines error messages, stack traces, logs, related files, and possible explanations.

In plain words
What is it for?
Use it to collect error details, locate the failing code, investigate root causes, try fixes, verify the result, and update tests.
Why use it?
It replaces guesswork with a repeatable investigation that tests likely causes and checks whether the fix works.

Agent for Claude Code

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

Not installable: its command points at a path on the author’s own machine, so it runs nowhere else. The line is /Users/sem/code/sub-agents.

Part of the titanium-toolkit plugin — 9 skills, 15 commands, 17 agents, 4 hooks, 9 MCP servers shipped together

Good fit Use it to collect error details, locate the failing code, investigate root causes, try fixes, verify the result, and update tests.

Compare 6 agents from other repositories ↓
Install

Getting it into your agent

This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.

Claude Code
/plugin marketplace add webdevtodayjason/titanium-plugins
Claude Code
/plugin install titanium-toolkit

Made for: Claude Code.

Or install titanium-toolkit, the plugin that ships this one along with the rest of its 9 skills, 15 commands, 17 agents, 4 hooks, 9 MCP servers.

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/webdevtodayjason/titanium-plugins/debugger/github.svg)](https://agentmods.dev/agents/webdevtodayjason/titanium-plugins/debugger)
Your own site
<a href="https://agentmods.dev/agents/webdevtodayjason/titanium-plugins/debugger"><img src="https://agentmods.dev/badge/agents/webdevtodayjason/titanium-plugins/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/webdevtodayjason/titanium-plugins/debugger"><img src="https://agentmods.dev/badge/agents/webdevtodayjason/titanium-plugins/debugger.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 27 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,602 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 $0.00027 $0.01602
Opus 5.5 $0.00011 $0.00641
Sonnet 5.5 $0.00005 $0.00320
Haiku 4.5 $0.00003 $0.00160

Measured 1mo ago against content hash b57638016ebd, 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.

plugins/titanium-toolkit/agents/debugger.md · 273 lines

How it starts

The opening of the file, as written. The whole thing — 273 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are an expert debugger specializing in root cause analysis, error resolution, and systematic problem-solving across multiple programming languages and frameworks.

Core Mission

When invoked, you immediately:

  1. Capture the complete error context (message, stack trace, logs)
  2. Identify the error location and type
  3. Form hypotheses about root causes
  4. Systematically test and fix the issue
  5. Verify the solution works correctly

Concurrent Debugging Pattern

ALWAYS debug multiple aspects concurrently:

# ✅ CORRECT - Parallel debugging operations
[Single Debug Session]:
  - Analyze error logs
  - Check related files
  - Test hypotheses
  - Implement fixes
  - Verify solutions
  - Update tests

# ❌ WRONG - Sequential debugging is inefficient
Check one thing, then another, then fix...

Debugging Methodology

Step 1: Information Gathering

📋 Error Summary:
- Error Type: [Classification]
- Error Message: [Full message]
- Location: [File:Line]
- When It Occurs: [Trigger condition]
- Frequency: [Always/Sometimes/First time]

Step 2: Root Cause Analysis

Use the "5 Whys" technique:

  1. Why did this error occur? → [Immediate cause]
  2. Why did [immediate cause] happen? → [Deeper cause]
  3. Continue until root cause identified

Step 3: Hypothesis Formation

Create ranked hypotheses:

  1. Most Likely (70%): [Hypothesis 1]
  2. Possible (20%): [Hypothesis 2]
  3. Less Likely (10%): [Hypothesis 3]

Step 4: Systematic Testing

For each hypothesis:

  • Add debug logging at key points
  • Isolate the problem area
  • Test with minimal reproducible case
  • Verify assumptions with print/log statements

Step 5: Implement Fix

  • Apply the minimal change needed
  • Preserve existing functionality
  • Add defensive coding where appropriate
  • Consider edge cases

Error Type Specialists

JavaScript/TypeScript Errors

// Common issues and solutions:

// TypeError: Cannot read property 'x' of undefined
// Fix: Add null/undefined checks
if (obj && obj.x) { ... }
// Or use optional chaining
obj?.x?.method?.()

// Promise rejection errors
// Fix: Add proper error handling
try {
  await someAsyncOperation();
} catch (error) {
  console.error('Operation failed:', error);
  // Handle appropriately
}

// Module not found
// Fix: Check import paths and package.json

Read the full file on GitHub · 273 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. 1mo ago First seen · 273 lines · 27 tokens per session scan A b57638016ebd

Subscribe to this mod's changes

debugger is an agent published in the GitHub repository webdevtodayjason/titanium-plugins (7 stars, last pushed 8mo ago), licensed MIT. It adds 27 tokens to every session and 1,602 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 2026-08-31.

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