Posthog

PostHog API Skill

Interact with PostHog via its REST API. Two types of endpoints:

• Public (POST-only, project API key): capture events, evaluate flags — no rate limits
• Private (personal API key): query, CRUD for all resources — rate limited

Setup

1. Get personal API key: https://us.posthog.com/settings/user-api-keys
2. Get project ID: https://us.posthog.com/settings/project#variables
3. Set env vars:

   export POSTHOG_API_KEY="phx_..."
   export POSTHOG_PROJECT_ID="12345"
   export POSTHOG_PROJECT_API_KEY="phc_..."  # optional, for capture/flags
   # For EU Cloud:
   # export POSTHOG_HOST="https://eu.posthog.com"
   # export POSTHOG_INGEST_HOST="https://eu.i.posthog.com"
   

4. Verify: bash scripts/posthog.sh whoami

Helper Script

scripts/posthog.sh wraps common operations. Run bash scripts/posthog.sh help for full usage.

Examples

# Capture an event
bash scripts/posthog.sh capture "signup" "user_123" '{"plan":"pro"}'

# Evaluate feature flags
bash scripts/posthog.sh evaluate-flags "user_123"

# HogQL query — top events last 7 days
bash scripts/posthog.sh query "SELECT event, count() FROM events WHERE timestamp >= now() - INTERVAL 7 DAY GROUP BY event ORDER BY count() DESC LIMIT 20"

# List persons
bash scripts/posthog.sh list-persons 10 | jq '.results[] | {name, distinct_ids}'

# List feature flags
bash scripts/posthog.sh list-flags | jq '.results[] | {id, key, active}'

# Create a feature flag
echo '{"key":"new-dashboard","name":"New Dashboard","active":true,"filters":{"groups":[{"rollout_percentage":50}]}}' | \
  bash scripts/posthog.sh create-flag

# List dashboards
bash scripts/posthog.sh list-dashboards | jq '.results[] | {id, name}'

Key Concepts

Two API types

• Public endpoints (/i/v0/e/, /batch/, /flags): Use project API key in body. No auth header. No rate limits.
• Private endpoints (/api/projects/:project_id/...): Use personal API key via Authorization: Bearer. Rate limited.

HogQL Queries

The query endpoint (POST /api/projects/:project_id/query/) is the most powerful way to extract data. Uses SQL-like HogQL syntax against tables: events, persons, sessions, groups, plus data warehouse tables.

Always include time ranges and LIMIT. Use timestamp-based pagination for large exports.

Rate Limits (private endpoints)

Limits apply per organization. On 429: back off and retry.

Domains

Events API (deprecated)

The /api/projects/:project_id/events/ endpoint is deprecated. Use HogQL queries or batch exports instead.

Direct curl

# Private endpoint
curl -H "Authorization: Bearer $POSTHOG_API_KEY" \
  "$POSTHOG_HOST/api/projects/$POSTHOG_PROJECT_ID/feature_flags/"

# HogQL query
curl -H "Authorization: Bearer $POSTHOG_API_KEY" \
  -H "Content-Type: application/json" \
  -X POST -d '{"query":{"kind":"HogQLQuery","query":"SELECT count() FROM events WHERE timestamp >= now() - INTERVAL 1 DAY"}}' \
  "$POSTHOG_HOST/api/projects/$POSTHOG_PROJECT_ID/query/"

# Capture event (public)
curl -H "Content-Type: application/json" \
  -X POST -d '{"api_key":"'$POSTHOG_PROJECT_API_KEY'","event":"test","distinct_id":"u1"}' \
  "$POSTHOG_INGEST_HOST/i/v0/e/"

Full API Reference

See references/api-endpoints.md for complete endpoint listing with parameters, body schemas, scopes, and response formats.

Sections: Public Endpoints (Capture, Batch, Flags), Private Endpoints (Persons, Feature Flags, Insights, Dashboards, Annotations, Cohorts, Experiments, Surveys, Actions, Session Recordings, Users, Definitions), Query API (HogQL).