PostHog

Open-source product analytics with session replay and feature flags.

Capabilities

Integration	Available	Notes
API	✓	Capture API, Query API, Feature Flags API
MCP	-	Not available
CLI	✓	posthog CLI for local development
SDK	✓	JavaScript, Python, Ruby, Go, etc.

Authentication

• Type: API Key (Personal or Project)
• Header: Authorization: Bearer {api_key}
• For capture: Project API Key in payload

Common Agent Operations

Capture event

POST https://app.posthog.com/capture/

{
  "api_key": "{project_api_key}",
  "event": "signup_completed",
  "distinct_id": "user_123",
  "properties": {
    "plan": "pro",
    "$current_url": "https://example.com/signup"
  }
}

Batch events

POST https://app.posthog.com/batch/

{
  "api_key": "{project_api_key}",
  "batch": [
    {"event": "pageview", "distinct_id": "user_1"},
    {"event": "signup", "distinct_id": "user_2"}
  ]
}

Get person by distinct_id

GET https://app.posthog.com/api/projects/{project_id}/persons/?distinct_id=user_123

Authorization: Bearer {api_key}

Query events (HogQL)

POST https://app.posthog.com/api/projects/{project_id}/query/

{
  "query": {
    "kind": "HogQLQuery",
    "query": "SELECT event, count() FROM events WHERE timestamp > now() - interval 7 day GROUP BY event ORDER BY count() DESC LIMIT 10"
  }
}

Get feature flag value

POST https://app.posthog.com/decide?v=3

{
  "api_key": "{project_api_key}",
  "distinct_id": "user_123"
}

Get insights

GET https://app.posthog.com/api/projects/{project_id}/insights/

Authorization: Bearer {api_key}

Get session recordings

GET https://app.posthog.com/api/projects/{project_id}/session_recordings/

Authorization: Bearer {api_key}

JavaScript SDK

// Initialize
posthog.init('PROJECT_API_KEY', {
  api_host: 'https://app.posthog.com'
});

// Identify user
posthog.identify('user_123', {
  email: 'user@example.com',
  plan: 'pro'
});

// Track event
posthog.capture('signup_completed', {
  method: 'email'
});

// Check feature flag
if (posthog.isFeatureEnabled('new-pricing')) {
  // Show new pricing
}

Key Features

• Event tracking - Product analytics
• Session replay - Watch user sessions
• Feature flags - Control feature rollout
• A/B testing - Built-in experiments
• HogQL - SQL-like query language
• Self-hostable - Run on your infrastructure

When to Use

• Product analytics with privacy focus
• Session replay for UX insights
• Feature flag management
• Self-hosted analytics needs
• Open-source requirements

Rate Limits

• Cloud: 10,000 events/second
• Self-hosted: Unlimited

Relevant Skills

• analytics-tracking
• ab-test-setup
• onboarding-cro