error-detective

An investigation assistant for finding error patterns, stack traces, and unusual events in logs and codebases, then linking related failures.

In plain words
What is it for?
Debugging applications, analyzing production incidents, correlating errors across services, writing log queries, and suggesting likely code locations.
Why use it?
It helps turn scattered error messages and timing changes into evidence about a likely root cause and ways to prevent recurrence.

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/nickcrew/claude-cortex/error-detective
Clone the repo
git clone --depth 1 https://github.com/NickCrew/Claude-Cortex
Per session 47 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 574 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 $0.00047 $0.00574
Opus 5 $0.00023 $0.00287
Sonnet 5 $0.00009 $0.00115
Haiku 4.5 $0.00005 $0.00057

Measured 2d ago against content hash 5d26e8d6a33f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, 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 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.

archive/agents/error-detective.md · 91 lines

What it actually says

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.

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 · 91 lines · 47 tokens per session scan A 5d26e8d6a33f

Subscribe to this mod's changes

error-detective is an agent published in the GitHub repository NickCrew/Claude-Cortex (36 stars, last pushed 2mo ago), licensed MIT. It adds 47 tokens to every session and 574 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.