Distillation

Date: Sep 16, 2026

• 🟡 (20:21) Further inspection of packages/gateway/src/pipeline.ts lines 9235–10053 showed terminal-output reconciliation that treats the output_item lifecycle as authoritative, tracks allowed incomplete indexes, and throws "Responses terminal output changed streamed item" when terminal output conflicts with accumulated streamed state.
• 🟡 (20:21) Reference-event handling in packages/gateway/src/pipeline.ts validates referenced items, tracks whether each reference is done, and distinguishes reference identities from synthetic identities using syntheticIdentities.
• 🟡 (20:21) The pipeline includes keepalive framing equivalent to streamResponsesPassthrough, converts formatted SSE frames to encoded output, and parses incoming SSE chunks by extracting lines prefixed with data: .
• 🟡 (20:21) Recall and follow-up execution are abort-aware: recall uses opts.onRecall, follow-up uses opts.runFollowUp, and late readers are cancelled through cancelLateReader() when execution is aborted or no longer needed.
• 🟡 (20:21) Synthetic Responses-stream generation emits the lifecycle sequence output_item.added → content_part.added → repeated output_text.delta, then completion events; synthesized items include output_index, item_id, content, and a default "completed" status when no explicit status is available.
• 🟡 (20:21) Synthetic terminal responses include usage accounting with inclusiveInputTokens, support incompleteDetails, and normalize raw output items into indexed records while preserving available content and status fields.
• 🟡 (20:21) Stream cancellation propagates the abort reason by calling currentPrincipalResponse.body?.cancel(signal.reason).