Shared UI Transcript Layer

Current status: packages/cli/src/ui/daemon/daemon-tui-adapter.ts is still present on main as a legacy experimental CLI-side adapter. This document describes the newer SDK-side shared UI transcript layer: reusable daemon event normalization and transcript primitives that any UI host can consume, including Web, TUI, IDE, and IM channels. CLI TUI, channel, and VS Code IDE migrations are follow-up work.

Overview

packages/sdk-typescript/src/daemon/ui/ adds a ui/* subpackage to the SDK. It turns the daemon SSE event stream into UI-renderable transcript blocks through reusable primitives:

Normalization (normalizer.ts): maps the daemon wire schema’s 43 known event types (see 09-event-schema.md) into 37 UI-friendly DaemonUiEventType semantic events such as assistant.text.delta, tool.update, and session.metadata.changed.
State machine (transcript.ts, store.ts): pure reducer plus subscribable store that projects UI events into an ordered DaemonTranscriptBlock[].
Renderers (render.ts, terminal.ts, toolPreview.ts): transcript blocks to HTML, terminal text, and tool preview strings. Hosts can use or replace them.
Conformance (conformance.ts): cross-host consistency tests used when channel, TUI, and IDE surfaces migrate to these primitives.

The first production consumer is packages/webui/src/daemon/ (#4328 ). Its React DaemonSessionProvider and transcript adapter let the web UI connect directly to daemon HTTP+SSE instead of only rendering host postMessage traffic. CLI TUI, channel base, and VS Code IDE can reuse the same layer later; ../daemon-ui/MIGRATION.md documents the v2 incremental migration guide.

Responsibilities

Normalize the 43 daemon wire events into a stable UI vocabulary (DaemonUiEventType) so renderers do not inspect rawEvent.data.
Keep daemon-monotonic SSE eventId as the primary ordering key so different clients render transcripts in the same order.
Use a pure reducer to produce transcript blocks, with selectors for pending permissions, current tool, approval mode, tool progress, and subagent children.
Provide baseline HTML and terminal renderers while allowing host-specific rendering.
Expose public constants such as DAEMON_PLAN_TOOL_CALL_ID for plan panels.
Preserve additive wire compatibility: unknown event types normalize to debug instead of being dropped.

Architecture

Package structure

File	Exports	Purpose
`packages/sdk-typescript/src/daemon/ui/index.ts`	Subpackage barrel	Public entry point
`ui/types.ts`	`DaemonUiEventType`, per-type `DaemonUiEvent*` interfaces, `DaemonTranscriptBlock`, `DaemonTranscriptState`, `DaemonUiToolProvenance`, `DAEMON_PLAN_TOOL_CALL_ID`	Types
`ui/normalizer.ts`	`normalizeDaemonEvent(evt) -> DaemonUiEvent`, `getSessionUpdatePayload(evt)`	Wire-to-UI mapping
`ui/transcript.ts`	`createDaemonTranscriptState()`, `appendLocalUserTranscriptMessage()`, `reduceDaemonTranscriptEvents()`, `rebuildDaemonTranscriptBlockIndex()`, selectors	State machine and selectors
`ui/store.ts`	`createDaemonTranscriptStore(initial?)`	Subscribable reducer store
`ui/toolPreview.ts`	`createDaemonToolPreview(toolEvent)`	Tool call summary text
`ui/render.ts`	`DaemonHtmlRenderOptions`, `DaemonRenderOptions`, render functions	HTML and generic rendering
`ui/terminal.ts`	Terminal-specific rendering	TUI preparation
`ui/conformance.ts`	Cross-host conformance suite	Migration parity tests
`ui/utils.ts`	Helpers such as `DaemonUiContentPart`	Internal shared utilities

`DaemonUiEventType` vocabulary

ui/types.ts defines 37 UI event types, grouped by domain.

Chat stream (Stage 1)

user.text.delta, user.image.delta, user.shell.command, assistant.text.delta, assistant.done, thought.text.delta
tool.update, shell.output, user.shell.output
permission.request, permission.resolved
model.changed, status, error, debug

Session metadata

session.metadata.changed, session.approval_mode.changed
session.available_commands, session.state_resync_required, session.replay_complete

Prompt lifecycle (cross-client)

prompt.cancelled, followup.suggestion

Workspace (Wave 3-4)

workspace.memory.changed, workspace.agent.changed
workspace.tool.toggled, workspace.settings.changed, workspace.initialized
workspace.mcp.budget_warning, workspace.mcp.child_refused
workspace.mcp.server_restarted, workspace.mcp.server_restart_refused

Auth flow (Wave 4 OAuth)

auth.device_flow.started, auth.device_flow.throttled, auth.device_flow.authorized
auth.device_flow.failed, auth.device_flow.cancelled

normalizeDaemonEvent maps the 43 daemon known wire events into this vocabulary. Unknown, unmodeled, or malformed event types normalize to debug and preserve rawEvent for host diagnostics.

Reducer and selectors


// Create initial state.
const state = createDaemonTranscriptState();
 
// Apply an SSE event sequence.
const next = reduceDaemonTranscriptEvents(state, daemonUiEvents);
 
// Selectors.
selectTranscriptBlocks(state); // all blocks
selectTranscriptBlocksOrderedByEventId(state); // ordered by eventId; preferred key
selectPendingPermissionBlocks(state);
selectCurrentTool(state);
selectApprovalMode(state);
selectToolProgress(state, toolCallId);
selectSubagentChildBlocks(state, parentBlockId);
isSubagentChildBlock(block);
formatBlockTimestamp(block);
formatMissedRange(state); // "you missed X" text after state_resync_required

Store

createDaemonTranscriptStore() provides subscribe and dispatch:


const store = createDaemonTranscriptStore();
store.subscribe(() => render(store.getState()));
store.dispatch(uiEvents); // internally runs the reducer

The web UI’s DaemonSessionProvider builds its React context on top of this store.

Flow

Single SSE event end-to-end

Hosts can stop at (E) and implement their own reducer, or consume (G) and the provided selectors. The web UI uses the full (B) -> (H) path. A migrated TUI can consume (G) and render with Ink-specific components.

`state_resync_required`

session.state_resync_required maps to a transcript “missed range” marker. UI code can call formatMissedRange(state) to render text such as “missed events X-Y”. The reducer continues applying later events, but marks affected blocks with resyncRecovery: true so renderers can add visual context. See 10-event-bus.md for ring-eviction and state_resync_required semantics.

Consumers

`packages/webui/src/daemon/`

This landed in #4328 .

File	Exports
`DaemonSessionProvider.tsx`	React `<DaemonSessionProvider />`; `useDaemonSession()`, `useDaemonTranscriptStore()`, `useDaemonTranscriptState()`, `useDaemonTranscriptBlocks()`, `useDaemonPendingPermissions()`, `useDaemonActions()`, `useDaemonConnection()` hooks; `DaemonConnectionStatus`, `DaemonConnectionState`, `DaemonSessionContextValue` types
`transcriptAdapter.ts`	Adapts SDK `DaemonTranscriptBlock` into the web UI’s `UnifiedMessage`, including markdown streaming chunk merge and tool call summaries
`index.ts`	Subpackage barrel

The web UI can now connect directly to daemon HTTP+SSE and render a transcript. The old ACPAdapter host postMessage path remains available.

Later migrations

../daemon-ui/MIGRATION.md provides a v2 incremental guide for web chat and web terminal adapters. It explicitly calls out that CLI TUI, channel base, and VS Code IDE are not migrated by that PR; each will move in follow-up PRs and use the conformance suite to preserve rendering parity.

Relationship to legacy `daemon-tui-adapter.ts`

Dimension	Legacy CLI `DaemonTuiAdapter`	New shared transcript layer
Package	`packages/cli/src/ui/daemon/`	`packages/sdk-typescript/src/daemon/ui/`
Public surface	`DaemonTuiAdapter`, `DaemonTuiUpdate`, `DaemonTuiSessionClient`	`DaemonUiEventType`, `reduceDaemonTranscriptEvents`, selectors
Scope	CLI Ink TUI only	Web, TUI, IDE, or IM UI
State shape	TUI-local update union	Pure transcript block list plus state fields
Ordering	`createdAt`	`eventId` (daemon-monotonic, consistent across clients)
Unknown wire type	Dropped in `reduceDaemonEventToTuiUpdates`	Normalized to `debug` and preserved
Tests	Single-package unit tests	Global conformance suite for cross-host parity

Dependencies

Upstream wire types: packages/sdk-typescript/src/daemon/events.ts (see 09-event-schema.md).
Real downstream consumer: packages/webui/src/daemon/.
Later migration targets: packages/cli/src/ui/, packages/channels/base/, and packages/vscode-ide-companion/src/services/daemonIdeConnection.ts.
Parallel references: ../daemon-ui/README.md, ../daemon-ui/MIGRATION.md, and ../daemon-client-adapters/web-ui.md.

Configuration

No runtime configuration. Reducers and selectors are pure functions.
Hosts choose their renderer: HTML (render.ts), terminal (terminal.ts), or custom rendering.
For debugging, render.ts supports includeRawEvent: true to include the raw wire frame in rendered output.

Caveats and known limits

daemon-tui-adapter.ts still exists. It is the CLI package’s legacy experimental adapter. New code should prefer SDK ui/*: normalizeDaemonEvent, reduceDaemonTranscriptEvents, and DaemonTranscriptBlock.
CLI TUI, channel base, and VS Code IDE are not migrated yet. They still maintain their own rendering logic. The docs/developers/daemon-client-adapters/ directory still has ide.md, channel-web.md, and the historical tui.md draft; the newer web-ui.md covers the web UI adapter design.
eventId is the primary ordering key. createdAt remains as a deprecated alias (clientReceivedAt). New code should use selectTranscriptBlocksOrderedByEventId(state). MIGRATION.md shows the code diff for switching from createdAt ordering to eventId ordering.
Unknown wire types normalize to debug. They are no longer dropped as in the old adapter. Renderers do not show debug by default; hosts must opt in to display it.
Bundle size: the ui/* subpackage is exported as an ESM subpath through @qwen-code/sdk/daemon and does not pull in React or DOM dependencies. React integration is only loaded when a web UI consumer uses DaemonSessionProvider.

References

packages/sdk-typescript/src/daemon/ui/types.ts (DaemonUiEventType vocabulary)
packages/sdk-typescript/src/daemon/ui/transcript.ts (reducer and selectors)
packages/sdk-typescript/src/daemon/ui/normalizer.ts (wire-to-UI mapping)
packages/sdk-typescript/src/daemon/ui/store.ts, render.ts, terminal.ts, toolPreview.ts, conformance.ts
packages/sdk-typescript/src/daemon/index.ts (ui/* re-export block)
packages/webui/src/daemon/DaemonSessionProvider.tsx, transcriptAdapter.ts
Upstream docs: ../daemon-ui/README.md, ../daemon-ui/MIGRATION.md, ../daemon-client-adapters/web-ui.md
Context PRs: #4328 (v1 transcript layer and web UI provider), #4353 (v2 unified completeness follow-up)