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error-patterns

Use this to quickly map log signatures to likely causes and fixes.

  • Skills
  • Development
  • 0

What it does and how to use it

A skill that teaches Claude Code to do development tasks well. It is packaged knowledge the model uses whenever it is relevant.

  1. Install the skill (command above).
  2. In Claude Code, describe what you need - the skill turns on by itself when the context fits.
  3. No commands to memorize: you talk in plain language and the skill does the rest.

Install (Claude Code)

mkdir -p .claude/skills/error-patterns-3 && curl -fsSL https://doutorai.pt/data/lib/skills__error-patterns-3.md -o .claude/skills/error-patterns-3/SKILL.md

Paste this command into the terminal, in your project folder, and the component installs automatically.

Content

# Error patterns (compact)

Use this to quickly map log signatures to likely causes and fixes.

| Log pattern | Likely cause | Quick fix |
| --- | --- | --- |
| `KeyError`, `not defined`, `missing environment` | Missing env var | Add env var in render.yaml or via MCP, then redeploy |
| `EADDRINUSE`, `listen EADDRINUSE` | Port binding conflict | Bind to `0.0.0.0:$PORT` |
| `Cannot find module`, `ModuleNotFoundError` | Missing dependency | Add dependency to manifest and rebuild |
| `ECONNREFUSED`, `connection refused` | DB not reachable | Verify DATABASE_URL and DB status |
| `Health check timeo

- 🔒 Full content on the Pro plan (€7.99/month) -

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