## Summary
Adds a `stop_workspace` tool to chatd so the model can recover from the
"workspace running but agent dead" failure mode (e.g. an OOM that leaves
the workspace running but the agent unreachable) by stopping and then
starting the workspace.
<img width="924" height="742" alt="image"
src="https://github.com/user-attachments/assets/279dedb6-6e29-4fe1-8754-3a1f01e538bf"
/>
## What changed
**New `stop_workspace` chatd tool**
(`coderd/x/chatd/chattool/stopworkspace.go`). Mirrors `start_workspace`:
shares `WorkspaceMu` to serialize with create/start, waits for any
in-progress build before issuing a stop, and is idempotent only after a
successful Stop transition. Failed stop builds re-attempt rather than
reporting success.
**New `chatStopWorkspace` coderd hook** (`coderd/exp_chats.go`). Mirrors
`chatStartWorkspace` minus the `RequireActiveVersion` gate. Stop should
not be blocked by template version policy.
**Differentiated recovery sentinels** (`coderd/x/chatd/chatd.go`).
`errChatAgentDisconnected` instructs the model to call `stop_workspace`
then `start_workspace`. `errChatDialTimeout` instructs a single retry,
then user escalation if it repeats. The previous single message
conflated transient and persistent failures.
**Two-signal recovery gate.** Recovery is only surfaced when a tool call
times out *and* a fresh DB read of the latest workspace agent says
`Disconnected`. The previous draft escalated on the DB read alone, which
would fire on a 30-second heartbeat blip (e.g. agent respawn) and prompt
a destructive stop/start unnecessarily.
**Cache-hit disconnected handling** now clears the cache and retries a
fresh dial before escalating, rather than returning the recovery
sentinel immediately. Latest-agent classification uses
`GetWorkspaceAgentsInLatestBuildByWorkspaceID` instead of the chat's
bound `AgentID`, so stale bindings after a rebuild don't misclassify.
**Shared chattool helpers** in `coderd/x/chatd/chattool/chattool.go`:
`latestWorkspaceBuildAndJob`, `publishBuildBinding`,
`provisionerJobTerminal`. Applied to both `start_workspace` and
`stop_workspace`.
## Notes
- Reverts an earlier draft that widened `ask_user_question` to root
standard turns. Plan-mode-only behavior is restored.
- The `stop_workspace` tool currently renders via the generic chat
tool-call UI. A follow-up frontend PR will prettify the `stop_workspace`
tool and style it like the `start_workspace` tool.
- Never-connected (`Timeout` status) agents are intentionally excluded
from recovery. They indicate template or startup failure, not the
running-but-dead case this PR targets.
Closes CODAGT-315
The chat tools (`read_template`, `create_workspace`) did not surface or
respect template version presets. Presets were invisible to the LLM and
preset parameter defaults were never applied at workspace creation. The
`toolsdk` MCP surface had the same gap (ref #24695, now subsumed here).
## What this changes
- **`read_template`** returns presets with `id`, `name`, `default`,
`description`, `icon`, `parameters`, and `desired_prebuild_instances`
(when set), so the LLM can pick the right preset and prefer
prebuilt-backed ones.
- **`create_workspace`** accepts a `preset_id`. The wsbuilder applies
preset parameter defaults and may claim a prebuilt workspace.
- **`start_workspace`** does *not* accept a preset. Presets are a
creation-time choice; subsequent starts use the workspace's existing
version and parameters. Users who need a specific preset or version on
an existing chat can create the workspace out-of-band (CLI / UI / API)
with the desired configuration and attach the chat to it.
- **`toolsdk`** gains `GetTemplate` (with presets including
`desired_prebuild_instances`), preset support on `CreateWorkspace`, and
preset + `rich_parameters` support on `CreateWorkspaceBuild`. The
`template_version_preset_id` description warns about preset/version
affinity.
> 🤖 Generated with [Coder Agents](https://coder.com/agents) and reviewed by a human.
Co-authored-by: Max schwenk <maschwenk@gmail.com>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Adds `coder exp chat context add` and `coder exp chat context clear`
commands that run inside a workspace to manage chat context files via
the agent token.
`add` reads instruction and skill files from a directory (defaulting to
cwd) and inserts them as context-file messages into an active chat.
Multiple calls are additive — `instructionFromContextFiles` already
accumulates all context-file parts across messages.
`clear` soft-deletes all context-file messages, causing
`contextFileAgentID()` to return `!found` on the next turn, which
triggers `needsInstructionPersist=true` and re-fetches defaults from the
agent.
Both commands auto-detect the target chat via `CODER_CHAT_ID` (already
set by `agentproc` on chat-spawned processes), or fall back to
single-active-chat resolution for the agent. The `--chat` flag overrides
both.
Also adds sub-agent context inheritance: `createChildSubagentChat` now
copies parent context-file messages to child chats at spawn time, so
delegated sub-agents share the same instruction context without
independently re-fetching from the workspace agent.
<details><summary>Implementation details</summary>
**New files:**
- `cli/exp_chat.go` — CLI command tree under `coder exp chat context`
**Modified files:**
- `agent/agentcontextconfig/api.go` — `ConfigFromDir()` reads context
from an arbitrary directory without env vars
- `codersdk/agentsdk/agentsdk.go` — `AddChatContext`/`ClearChatContext`
SDK methods
- `coderd/workspaceagents.go` — POST/DELETE handlers on
`/workspaceagents/me/chat-context`
- `coderd/coderd.go` — Route registration
- `coderd/database/queries/chats.sql` — `GetActiveChatsByAgentID`,
`SoftDeleteContextFileMessages`
- `coderd/database/dbauthz/dbauthz.go` — RBAC implementations for new
queries
- `coderd/x/chatd/subagent.go` — `copyParentContextFiles` for sub-agent
inheritance
- `cli/root.go` — Register `chatCommand()` in `AGPLExperimental()`
**Auth pattern:** Uses `AgentAuth` (same as `coder external-auth`) —
agent token via `CODER_AGENT_TOKEN` + `CODER_AGENT_URL` env vars.
</details>
> 🤖 Generated by Coder Agents
---------
Co-authored-by: Michael Suchacz <203725896+ibetitsmike@users.noreply.github.com>
Ethan