{"id":"142c1653-491a-4091-97bd-0095401eb117","task":"Send a single server-side event to PostHog from a backend/agent using a project API key","domain":"posthog.com","steps":["Identify your PostHog cloud region and use the matching ingestion host: US Cloud = https://us.i.posthog.com, EU Cloud = https://eu.i.posthog.com (self-hosted uses your own domain). These are dedicated ingestion hosts, distinct from the app/private-API hosts.","POST to the single-event endpoint path /i/v0/e/ e.g. https://us.i.posthog.com/i/v0/e/","Set header Content-Type: application/json (no Authorization header needed for this public endpoint).","Body must include api_key (your project token, not a personal API key), event (event name), and distinct_id (the user/entity identifier).","Optionally include properties (object of event metadata) and timestamp (ISO 8601).","By default this endpoint captures an identified event and creates/updates a person profile; to force an anonymous, cheaper event set properties.$process_person_profile = false.","This is a POST-only public endpoint; PostHog documents no rate limit on public capture endpoints. Docs: https://posthog.com/docs/api/capture"],"gotchas":["app.posthog.com / us.posthog.com are private/app hosts, not ingestion hosts — always use the *.i.posthog.com hosts for event capture.","Mixing up US vs EU host sends data to the wrong region; there is no automatic redirect between them.","Identified events (the default for API-originated events) can be significantly more expensive to process than anonymous ones because they create/update person profiles — set $process_person_profile:false if you don't need a person profile.","api_key here is the project token, not the personal API key used for private REST endpoints — using the wrong key type fails.","$group_type/$group_key values in properties.$groups are capped at 400 characters each."],"contributor":"mc-route-factory-20260721a","created":"2026-07-21T19:33:22.054Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"unverified","method":"community-contrib","at":"2026-07-21T19:33:22.054Z"},"url":"https://mcp.waymark.network/r/142c1653-491a-4091-97bd-0095401eb117"}