Desktop sessions can receive task tools, background-agent lifecycle events, and child tool stream events in the same turn. The UI now keeps root Agent cards separate from task-management tools, preserves parent links when later stream events omit them, and surfaces completed background-agent result text from task notifications.
Constraint: Existing desktop session history can contain task-notification XML and live WS events with incomplete parent metadata.
Rejected: Render local_agent lifecycle messages as standalone cards | duplicates the Agent tool card and makes ownership unclear.
Confidence: high
Scope-risk: moderate
Directive: Do not collapse Agent and TaskCreate/TaskUpdate root tools into one generic group without checking multi-agent screenshots.
Tested: SKIP_INSTALL=1 PRESERVE_TAURI_TARGET=1 ./desktop/scripts/build-macos-arm64.sh
Tested: Real gpt-5.5 desktop E2E sessions under /tmp/cc-haha-subagent-e2e-20260519-025454 for 3 subagents, child tools, result dialog, and background Bash completion.
Not-tested: Full bun run verify gate.
The session inspector now asks the resumed CLI for a fast structural context estimate instead of forcing the full token-counting API path. This preserves live CLI state for system prompt, tools, MCP tools, skills, and messages while avoiding the 20s timeout that made historical sessions appear stuck or fall back to transcript-only estimates.
Constraint: Inspector requests must return quickly for third-party providers and historical resumed sessions.
Rejected: Increase the server timeout | the slow path can still block on provider token counting and keeps the UI feeling broken.
Confidence: high
Scope-risk: narrow
Directive: Keep interactive inspector context on the estimateOnly control path unless the UI explicitly supports a slow precise refresh.
Tested: bun test src/server/__tests__/conversations.test.ts -t 'structured session inspection|Sonnet 4.6 transcript usage'
Tested: cd desktop && bun run test -- --run src/i18n/index.test.tsx
Tested: cd desktop && bun run build
Tested: direct /api/sessions/:id/inspection?includeContext=1 returned live context in 0.046867s with System prompt, System tools, MCP tools, Messages
Tested: agent-browser automation verified no loading/error and visible System prompt/System tools/MCP tools/Messages
Not-tested: bare root tsc --noEmit, because current tsconfig scans existing desktop/src-tauri/target generated binary assets unrelated to this change
Desktop slash commands now separate local UI panels from CLI turn execution. The session inspector exposes status, usage, and context data from the active session, including transcript and context fallbacks, so /status, /cost, and /context can render structured desktop UI instead of raw terminal text. The inspector and help surfaces now use the existing desktop i18n catalogs for English and Chinese labels.
Constraint: Desktop read-only slash commands must not spawn duplicate CLI processes or depend on submitting a normal user turn.
Rejected: Render raw CLI command text in chat | it keeps terminal-specific layout constraints and does not fit the desktop panel UX.
Confidence: high
Scope-risk: moderate
Directive: Keep /status, /cost, and /context routed through the local inspector unless the CLI exposes a structured interactive command protocol.
Tested: cd desktop && bun run lint
Tested: cd desktop && bun test src/components/chat/composerUtils.test.ts
Tested: bun test src/server/__tests__/conversations.test.ts
Tested: cd desktop && bun run build
Tested: agent-browser smoke test on http://127.0.0.1:2024/ for /context localized inspector
Tested: git diff --check
Not-tested: Full packaged Tauri desktop build.
