Stream Claude Code subagent activity inline in the transcript

docs/claude-protocol.md

@@ -30,6 +30,7 @@ NDJSON both ways: one JSON object per line on stdin and stdout. Non-JSON stdout
 - `--include-partial-messages` adds `stream_event` lines wrapping the raw API stream (`message_start`, `content_block_start`, `content_block_delta` with `text_delta`, `content_block_stop`, `message_delta`, `message_stop`), each with `parent_tool_use_id` (set inside subagents). The complete `assistant` event for a block still arrives, before that block's `content_block_stop`. Transcripts leave `stream_event` lines out.
 - The `init` event arrives with the first turn, not at launch, so the session ID is unknown until the first message is sent.
 - While a tool runs, `tool_progress` lines with `"heartbeat": true`, the tool's `elapsed_time_seconds`, and a `parent_tool_use_id` naming the tool call arrive every 30 seconds. A Bash call also brings `system` `task_started` and `task_notification` lines around it.
+- Subagents (the `Agent` tool, listed in `init` tools as `Task`): `system` `task_started` (`task_type` `local_agent`, `tool_use_id` naming the `Agent` call, `subagent_type`, `description`, `prompt`, `is_backgrounded`), `task_progress` (`description` of what it is doing), `task_updated` (by `task_id` only), and `task_notification` (`status`, `summary`). `assistant` and `user` lines from inside the subagent carry `parent_tool_use_id` set to the `Agent` call's ID, plus `agent_id`, `subagent_type` and `task_description`. A foreground subagent (`run_in_background: false`) sends only its prompt this way, as a `user` text block, and its final report arrives as the `Agent` call's `tool_result`. A background one (the default) streams all its assistant and tool-result lines; the `Agent` call's `tool_result` comes back at once saying it launched, the turn can end with its own `result` while the subagent runs, and when the subagent finishes the CLI starts another turn by itself, ending in a second `result` carrying `origin.kind` `task-notification`.
 - Lines that aren't a JSON object, don't parse, or have a `type` not in `knownTypes` (`internal/claude/session.go`) go to `Options.OnBadLine`; lines that parse are still delivered as events whatever their type.
 
 ## Control channel

docs/operations.md

@@ -96,9 +96,9 @@ Agent health is `internal/agents/health.go`:
 
 The Status modal (the navbar's **Status** button; Esc, ×, a click outside it or following a task link closes it) shows, from the top: a Problems section only when there are zombies or protocol errors (one line per zombie, and per vendor the error count with the latest line folded under it); running turns against each cap, each running turn with the time since its process's last event and `stuck` or `exited` when it is; queued turns in order, both linking to their tasks; each vendor's rate-limit status with its reset time and per-window utilization, and the server counts. It refetches the status when a `session.created`, `session.state`, `task.*`, `project.created` or `admin.health` event arrives, when an `agent.vendor` event carries a `rate_limit_event`, and when the SSE stream reconnects. Other events advance the last-event seq it shows, and any event carrying a process's `agent_session_id` (stored or not, such as `agent.delta`) moves that process's last-event time forward, re-rendering at most once a second per process. A re-render keeps the scroll position and which folded lines are open. There is no timer, so "time since last event" and the "in 2h 10m" beside a reset time are as of the last render; a process going quiet long enough to be stuck shows up when the next health check broadcasts `admin.health`.
 
-Agent activity becomes events with `agent_session_id` set: `user.message`, `agent.message`, `agent.thinking`, `agent.tool_call`, `agent.tool_result`, `turn.ended`, `session.state`, `session.model`, and `session.context`. Anything else Claude Code emits (rate-limit status, task progress, state changes) is recorded unchanged as `agent.vendor`. The one exception is partial output: each top-level `text_delta` is broadcast to SSE clients as an `agent.delta` event (`payload.text`, `seq` 0) that is never stored, and the transcript grows a live message from them until the finished `agent.message` replaces it. A `turn.ended` event carries `inbox_item_id` when its final message was filed as a `report` item. `session.context` records the context size whenever it changes: `used` is the last assistant message's input, cache-read, cache-creation and output tokens, and `window` is the model's context window from the turn's `result` (`modelUsage[model].contextWindow`), so it is 0 until the session's first turn after a server start ends. The task header's **Compact** button shows the latest one as a background fill across the button, proportional to the window, tinted amber from 70% and red from 90%; the exact count is in its tooltip.
+Agent activity becomes events with `agent_session_id` set: `user.message`, `agent.message`, `agent.thinking`, `agent.tool_call`, `agent.tool_result`, `turn.ended`, `session.state`, `session.model`, and `session.context`. Anything else Claude Code emits (rate-limit status, task progress, state changes) is recorded unchanged as `agent.vendor`. The one exception is partial output: each top-level `text_delta` is broadcast to SSE clients as an `agent.delta` event (`payload.text`, `seq` 0) that is never stored, and the transcript grows a live message from them until the finished `agent.message` replaces it. A `turn.ended` event carries `inbox_item_id` when its final message was filed as a `report` item. Activity inside a subagent (`agent.message`, `agent.thinking`, `agent.tool_call`, `agent.tool_result`) carries `payload.parent_tool_use_id`, the ID of the tool call that started the subagent, and never updates `session.context`. `session.context` records the context size whenever it changes: `used` is the last assistant message's input, cache-read, cache-creation and output tokens, and `window` is the model's context window from the turn's `result` (`modelUsage[model].contextWindow`), so it is 0 until the session's first turn after a server start ends. The task header's **Compact** button shows the latest one as a background fill across the button, proportional to the window, tinted amber from 70% and red from 90%; the exact count is in its tooltip.
 
-Messages byre itself sends an agent (actor `byre`: the restart notice, Sync and Merge prompts, Compact's handoff request and the continuation's handoff) show collapsed like a tool call, labelled `byre` with the first line as the brief; expanding it shows the full text. The transcript view has an accent border while the session is `running`, and a braille spinner on its last line, cycling ⠋⠙⠹⠸⠼⠴⠦⠧⠇⠏ every 0.8s. It is one element with one CSS animation: the ten frames are drawn side by side in an inline SVG used as the `.spinner` mask over an accent background, and the `braille` keyframes in `web/style.css` step the mask position through them. Orion freezes animated GIFs and per-dot `step-end` opacity animations partway through a turn, so it stays a single element with a single animation. Consecutive tool calls (with any thinking between them) collapse into one group whose summary counts calls per tool and file, and file paths show relative to the worktree. A turn's final message that is at least half visible in the transcript while the page is visible dismisses its `report` inbox item, as the viewing user. Selecting a task that has never had a session focuses the composer. In the composer, Enter sends and Shift-Enter adds a newline; unsent text is kept per task in memory, so it survives switching tabs or tasks but not a page reload. The composer has no `@`-file mentions or path picker: text reaches the agent exactly as typed (stream-json doesn't expand `@path` the way the interactive CLI does), and the agent reads any file the message names with its own tools. The composer is the same whether or not the task has a live session: Send posts to the session's messages, or starts a session with the text when there is none or the last one completed. A sent message shows at once as a "sending…" bubble, replaced by the server's `user.message` event with the same text when it arrives, and removed (text and images back in the composer) if the request fails.
+Messages byre itself sends an agent (actor `byre`: the restart notice, Sync and Merge prompts, Compact's handoff request and the continuation's handoff) show collapsed like a tool call, labelled `byre` with the first line as the brief; expanding it shows the full text. The transcript view has an accent border while the session is `running`, and a braille spinner on its last line, cycling ⠋⠙⠹⠸⠼⠴⠦⠧⠇⠏ every 0.8s. It is one element with one CSS animation: the ten frames are drawn side by side in an inline SVG used as the `.spinner` mask over an accent background, and the `braille` keyframes in `web/style.css` step the mask position through them. Orion freezes animated GIFs and per-dot `step-end` opacity animations partway through a turn, so it stays a single element with a single animation. Consecutive tool calls (with any thinking between them) collapse into one group whose summary counts calls per tool and file, and file paths show relative to the worktree. A Claude Code subagent call (the `Agent` or `Task` tool) stands on its own, collapsed, labelled with its `subagent_type` and `description`; expanding it shows the prompt and the call's result. Its summary carries a status from the `agent.vendor` `system` events whose `tool_use_id` names it (`task_started`: running, or running in the background; `task_progress`: its `description`; `task_notification`: its `status`, red unless `completed`). The subagent's own messages, thinking and tool calls (events whose `parent_tool_use_id` names the call) stream inline with the main agent's, in arrival order, each marked `↳ <subagent_type>` with the description as its tooltip; its messages also get an accent rule down their left edge. A run of tool calls groups only calls from the same agent, so a call from another agent starts a new group. A subagent's messages never end the main agent's live message, count as a turn's final message or hide a quiet turn. Claude Code streams a background subagent's activity, but for a foreground one only its prompt, so a foreground subagent shows only as its call, its status and its result. A turn's final message that is at least half visible in the transcript while the page is visible dismisses its `report` inbox item, as the viewing user. Selecting a task that has never had a session focuses the composer. In the composer, Enter sends and Shift-Enter adds a newline; unsent text is kept per task in memory, so it survives switching tabs or tasks but not a page reload. The composer has no `@`-file mentions or path picker: text reaches the agent exactly as typed (stream-json doesn't expand `@path` the way the interactive CLI does), and the agent reads any file the message names with its own tools. The composer is the same whether or not the task has a live session: Send posts to the session's messages, or starts a session with the text when there is none or the last one completed. A sent message shows at once as a "sending…" bubble, replaced by the server's `user.message` event with the same text when it arrives, and removed (text and images back in the composer) if the request fails.
 
 The task switcher (⌘K, or the navbar crumb) lists active tasks with their session state and open inbox item count, live while it is open. Tasks with inbox items come first; within each group, the task least recently visited in this browser comes first (never-visited tasks before all others, ties in the server's order: projects by name, tasks newest first). Visit times are kept in the browser's localStorage under `byre.visits`, stamped when a task is selected and again when it is left. After the tasks come the projects, one row each; picking one points the right pane at the project with no task, on the Project tab. Typing filters both and adds a last row that creates a task with the typed text as its title, in the right pane's project (the first project when there is none); Enter picks the highlighted row. Picking a task points the right pane at it on the Transcript tab (see "Lead agent").