Distillation

Date: Sep 14, 2026

• 🟡 (08:58) The session-message projector maintains messages: SessionMessage.Message[] and exposes an adapter operation updateShell: (shell: SessionMessage.Shell) => Effect.Effect<void>.
• 🟡 (08:58) Projection ownership is enforced through helpers including activeShellIndex(callID), updateOwnedAssistant(assistantMessageID, ...), latestText(...), and latestTool(...); mutations are ignored when the targeted current message is not an assistant, implementing the rule that newer turns supersede stale incomplete assistant rows rather than resuming an older projection.
• 🟡 (08:58) The projector handles step lifecycle events by creating an assistant projection on session.next.step.started, then applying finish, cost, token accounting, snapshot/files, completion time, or error data from terminal step events to the assistant identified by assistantMessageID.
• 🟡 (08:58) Text streaming is projected through started/delta/ended boundaries: session.next.text.delta locates the latest matching text content by textID, while final boundaries update the owned assistant rather than an arbitrary older assistant row.
• 🟡 (08:58) Tool lifecycle projection handles session.next.tool.called, session.next.tool.progress, success, and failure transitions. Calls create assistant tool content with decoded input; progress updates running structured and content; terminal states preserve provider result metadata, structured/content output, optional result, and error or success details, locating the latest matching tool by callID.
• 🟡 (08:58) Reasoning and compaction content are projected with started/delta/ended event boundaries and are scoped to the owning assistant via assistantMessageID.
• 🟡 (08:58) Shell projection uses callID to find the active shell and updates shell output/state through the adapter rather than appending unrelated shell rows.
• 🟡 (08:58) Explicit no-op projector handlers include "session.next.moved": () => Effect.void and "session.next.revert.staged": () => Effect.void.