Error Tracking Python Agent Skill

PostHog error tracking for Python

This skill helps you add PostHog error tracking to Python applications.

Reference files

• references/python.md - Python error tracking installation - docs
• references/fingerprints.md - Fingerprints - docs
• references/alerts.md - Send error tracking alerts - docs
• references/monitoring.md - Monitor and search issues - docs
• references/assigning-issues.md - Assign issues to teammates - docs
• references/upload-source-maps.md - Upload source maps - docs

Consult the documentation for API details and framework-specific patterns.

Key principles

• Environment variables: Always use environment variables for PostHog keys and host URLs. Never hardcode them.
• Minimal changes: Add error tracking alongside existing error handling. Don't replace or restructure existing error handling code.
• Autocapture first: Enable exception autocapture in the SDK initialization before adding manual captures.
• Source maps: Upload source maps so stack traces resolve to original source code, not minified bundles.
• Manual capture for boundaries: Use captureException() at error boundaries and catch blocks for errors that don't propagate to the global handler.

Framework guidelines

• Remember that source code is available in the venv/site-packages directory
• posthog is the Python SDK package name
• Install dependencies with pip install posthog or pip install -r requirements.txt and do NOT use unquoted version specifiers like >= directly in shell commands
• In CLIs and scripts: MUST call posthog.shutdown() before exit or all events are lost
• Always use the Posthog() class constructor (instance-based API) instead of module-level posthog.api_key config
• Always include enable_exception_autocapture=True in the Posthog() constructor to automatically track exceptions
• NEVER send PII in capture() event properties — no emails, full names, phone numbers, physical addresses, IP addresses, or user-generated content
• PII belongs in identify() person properties, NOT in capture() event properties. Safe event properties are metadata like message_length, form_type, boolean flags.
• Register posthog_client.shutdown with atexit.register() to ensure all events are flushed on exit
• The Python SDK has NO identify() method — use posthog_client.set(distinct_id=user_id, properties={...}) to set person properties, or use identify_context(user_id) within a context