error-detective

error-detective is a skill for Claude Code, Codex from beel-collab/presets.dev. It costs 26 tokens per session (410 once invoked), scanned A, a copy of error-detective, MIT.

A debugging guide for finding error patterns, stack traces, and unusual events in logs and code. It also links related errors across systems to help identify likely causes.

In plain words
What is it for?
Use it to extract errors with search patterns, study stack traces, compare errors over time, query log systems such as Elasticsearch or Splunk, and investigate error spikes.
Why use it?
It reduces the need to inspect scattered logs manually when an application fails or behaves strangely. It helps trace symptoms back to changes, repeated patterns, and cascading failures.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to extract errors with search patterns, study stack traces, compare errors over time, query log systems such as Elasticsearch or Splunk, and investigate error spikes.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/beel-collab/presets.dev/error-detective
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 beel-collab/presets.dev --skill error-detective
Clone the repo
git clone --depth 1 https://github.com/beel-collab/presets.dev

Made for: Claude Code, Codex.

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 error-detective

README.md
[![agentmods](https://agentmods.dev/badge/skills/beel-collab/presets.dev/error-detective.svg)](https://agentmods.dev/skills/beel-collab/presets.dev/error-detective)
Your own site
<a href="https://agentmods.dev/skills/beel-collab/presets.dev/error-detective"><img src="https://agentmods.dev/badge/skills/beel-collab/presets.dev/error-detective.svg" alt="Measured on agentmods" height="20"></a>
Per session 26 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 410 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 88% 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 $0.00026 $0.00410
Opus 5 $0.00013 $0.00205
Sonnet 5 $0.00005 $0.00082
Haiku 4.5 $0.00003 $0.00041

Measured 4d ago against content hash 1003b73286a1, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

error-detective 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 4d 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

88% identical to error-detective — 21 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.

claude/skills/development/error-detective/SKILL.md · 58 lines

What it actually says

Use this skill when

  • Working on error detective tasks or workflows
  • Needing guidance, best practices, or checklists for error detective

Do not use this skill when

  • The task is unrelated to error detective
  • You need a different domain or tool outside this scope

Instructions

  • Clarify goals, constraints, and required inputs.
  • Apply relevant best practices and validate outcomes.
  • Provide actionable steps and verification.
  • If detailed examples are required, open resources/implementation-playbook.md.

You are an error detective specializing in log analysis and pattern recognition.

Focus Areas

  • Log parsing and error extraction (regex patterns)
  • Stack trace analysis across languages
  • Error correlation across distributed systems
  • Common error patterns and anti-patterns
  • Log aggregation queries (Elasticsearch, Splunk)
  • Anomaly detection in log streams

Approach

  1. Start with error symptoms, work backward to cause
  2. Look for patterns across time windows
  3. Correlate errors with deployments/changes
  4. Check for cascading failures
  5. Identify error rate changes and spikes

Output

  • Regex patterns for error extraction
  • Timeline of error occurrences
  • Correlation analysis between services
  • Root cause hypothesis with evidence
  • Monitoring queries to detect recurrence
  • Code locations likely causing errors

Focus on actionable findings. Include both immediate fixes and prevention strategies.

Limitations

  • Use this skill only when the task clearly matches the scope described above.
  • Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
  • Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.
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. 4d ago First seen · 58 lines · 26 tokens per session scan A 1003b73286a1

Subscribe to this mod's changes

error-detective is a skill published in the GitHub repository beel-collab/presets.dev (2 stars, last pushed 4mo ago), licensed MIT. It adds 26 tokens to every session and 410 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 88% identical to error-detective, differing in 21 lines, and is treated as a copy.

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