Document call_summary event_details (call_id) on the Preview spec

[mailsongabriel]

What changed

Documents the call_summary variant of event_details on conversation parts, added by intercom/intercom#552808 (issue intercom/intercom#552202).

A phone conversation can contain several calls, and therefore several call_summary parts side by side. Nothing in the API said which call each summary described — integrators were reduced to matching call.initiated_at against the nearest call_summary.created_at. The monolith PR exposes the call id on the part:

"event_details": { "call_id": "3822007689" }

The id matches the id returned by the Calls API and by the call.started, call.ended, call.recording_available and call.transcription_available webhook topics, so it is a direct join key.

Spec changes:

• new call_summary schema in components/schemas, following the existing Part type - <part_type> convention used by conversation_tags_updated, snoozed, priority_changed and the SLA variants
• added to the event_details anyOf

No inline response examples needed updating: this adds a variant to the anyOf rather than a field to conversation_part, and none of the existing part examples are call_summary parts.

Which API versions are affected

Preview (descriptions/0/api.intercom.io.yaml) only. The monolith change is registered on the unstable/preview version, so it is not visible on any pinned stable version yet.

Validation

fern check reports the same 3 errors and 300 warnings before and after this change (all pre-existing, in preview/conversationsAttributes.yml and preview/articles.yml) — this change introduces none.

_{Generated with Claude Code}