debug

debug is a skill for Claude Code from softspark/ai-toolkit. It costs 34 tokens per session (2,040 once invoked), scanned A, original, Apache-2.0.

A guided method for investigating application errors using logs, health checks, error details, and testable explanations. It helps trace a visible failure back to its underlying cause.

In plain words
What is it for?
Use it to investigate bugs, reproduce failures, inspect application logs, and narrow down the files or code paths that need attention.
Why use it?
It reduces guesswork when a program fails or behaves unexpectedly. Parsed error output can point to the likely error type, relevant files, and possible causes.

Skill for Claude Code

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

Part of the ai-toolkit plugin — 115 skills, 44 agents, 14 hooks shipped together

Good fit Use it to investigate bugs, reproduce failures, inspect application logs, and narrow down the files or code paths that need attention.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/softspark/ai-toolkit/debug
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.

Any agent
npx skills add softspark/ai-toolkit --skill debug
Clone the repo
git clone --depth 1 https://github.com/softspark/ai-toolkit

Made for: Claude Code.

Or install ai-toolkit, the plugin that ships this one along with the rest of its 115 skills, 44 agents, 14 hooks.

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 debug

README.md
[![agentmods](https://agentmods.dev/badge/skills/softspark/ai-toolkit/debug/github.svg)](https://agentmods.dev/skills/softspark/ai-toolkit/debug)
Your own site
<a href="https://agentmods.dev/skills/softspark/ai-toolkit/debug"><img src="https://agentmods.dev/badge/skills/softspark/ai-toolkit/debug/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 debug

Your own site · 80×15
<a href="https://agentmods.dev/skills/softspark/ai-toolkit/debug"><img src="https://agentmods.dev/badge/skills/softspark/ai-toolkit/debug.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 34 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,040 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00034 $0.02040
Opus 5.5 $0.00014 $0.00816
Sonnet 5.5 $0.00007 $0.00408
Haiku 4.5 $0.00003 $0.00204

Measured 20d ago against content hash 7421020eda84, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

debug scanned grade A 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 20d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/error-parser.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl -sf http://localhost:{port}/health
app/skills/debug/SKILL.md · 222 lines

How it starts

The opening of the file, as written. The whole thing — 222 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Debug Helper

$ARGUMENTS

Systematic debugging for application issues.

Project context

  • Recent logs: !docker compose logs --tail 20 2>/dev/null || tail -20 logs/*.log 2>/dev/null || echo "no-logs-found"

Automated Error Parsing

Pipe error output through the error parser for structured diagnosis:

# Pipe from failing command
your_command 2>&1 | python3 ${CLAUDE_SKILL_DIR}/scripts/error-parser.py

# Or from a log file
cat /var/log/app/error.log | python3 ${CLAUDE_SKILL_DIR}/scripts/error-parser.py

The script outputs JSON with:

  • language: detected language (python/node/go/php)
  • error_type: extracted error class (e.g., ModuleNotFoundError)
  • message: the error message text
  • category: classification (import, reference, type, connection, timeout, memory, permission, syntax)
  • stack_frames: parsed file/line/function from the stack trace
  • files_to_check: unique files from the trace, ordered by relevance
  • common_causes: likely root causes for this error category

Use the parsed output to focus investigation on the right files and hypotheses.


Methodology — The Iron Law

NO FIXES WITHOUT ROOT CAUSE INVESTIGATION FIRST

Random fixes waste time and create new bugs. Quick patches mask underlying issues. Complete each phase before proceeding to the next.

Phase 1 — Root Cause Investigation

Read error messages and stack traces completely. Reproduce reliably (or gather more data — don't guess). Check recent changes (git diff, new deps, config). For multi-component systems: log boundary in/out at each layer, identify WHERE it breaks before WHY.

Phase 2 — Pattern Analysis

Find similar working code in the same codebase. Compare against references completely, not skimming. List every difference, however small.

Phase 3 — Hypothesis & Testing

Form a single hypothesis ("X is the root cause because Y"). Test minimally — smallest possible change, one variable at a time. Verify before continuing — if it didn't work, form a NEW hypothesis. Don't stack fixes on top of fixes.

Read the full file on GitHub · 222 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 20d ago Changed 7421020eda84
  2. 1mo ago First seen · 222 lines · 34 tokens per session scan A ed8d621c52fa

Subscribe to this mod's changes

debug is a skill published in the GitHub repository softspark/ai-toolkit (180 stars, last pushed 8d ago), licensed Apache-2.0. It adds 34 tokens to every session and 2,040 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

Related

Other skills, from other repositories

cline-fix-volatile-msg

Ladder-aware Cline Anthropic caching — verify the rolling read/write ladder on the wire, then add the tools breakpoint and tune TTL. Updated for the 2026-08 AI-SDK monorepo.

OnlyTerp/prompt-cache-skills · 50 tokens

opencode-detect-openai-compat

OpenCode's caching detection misses OpenAI-compatible proxies routing to Anthropic/Bedrock. Broaden the predicate.

OnlyTerp/prompt-cache-skills · 32 tokens

cline-pin-timestamp

Cline's system prompt includes a timestamp that may be recomputed per request, invalidating the system-prompt cache.

OnlyTerp/prompt-cache-skills · 29 tokens

continue-fix-volatile-msg

Ladder-aware Continue Anthropic caching — verify the rolling ladder on the wire, then enable it by default and add TTL coverage.

OnlyTerp/prompt-cache-skills · 33 tokens

log-analyzer

Senior-SRE log analysis specialist. Use when investigating incidents from logs, triaging error spikes, extracting timelines, correlating distributed traces, or separating signal from noise across plain-text, JSON (slog/zap), syslog, journald, container, and Kubernetes logs. ALWAYS use when the user asks to "analyze…

johnqtcg/awesome-skills · 138 tokens

incident-postmortem

Incident post-mortem specialist for writing blameless post-mortems, extracting timelines from logs/events, conducting root cause analysis (5-Why, fishbone), classifying severity, and generating tracked action items. ALWAYS use when writing a post-mortem, reviewing an incident, extracting a timeline, performing root…

johnqtcg/awesome-skills · 98 tokens