How to Design Async Summarization APIs for Marketplace Sales Calls

A technical guide outlines best practices for building call summarization APIs that handle multiple documents and CRM exports in marketplace sales environments. The core recommendation is to use durable async jobs when several transcripts must be processed together into a single verified CRM output, reserving inline requests only for single, short documents with tight latency requirements. The architecture requires a four-identity result model covering job, input document, processing attempt, and export to prevent duplicate submissions, retry overwrites, or silent omissions. An explicit state machine with states such as accepted, running, completed, and cancelled is advised to give callers a clear and unambiguous contract. TypeScript type definitions are provided to ensure partial completion is visible and every exported CRM action remains traceable back to its source document.