Closes
[CODAGT-629](https://linear.app/codercom/issue/CODAGT-629/agents-can-get-stuck-and-ignore-stop-or-nudge).
A stuck chat had these logs associated with it:
```
1781735334322 2026-06-17T22:28:54.322Z 2026-06-17 22:28:54.322 [debu] coderd.chatd.processor: workspace context build: workspace agent not resolvable chat_id=d4524ebb-4494-47df-b258-d933c0248942 owner_id=d96bf761-3f94-46b3-a1da-6316e2e4735d
1781735334298 2026-06-17T22:28:54.298Z 2026-06-17 22:28:54.298 [debu] coderd.chatd.processor: plan path instruction: agent not reachable chat_id=d4524ebb-4494-47df-b258-d933c0248942 owner_id=d96bf761-3f94-46b3-a1da-6316e2e4735d chat_id=d4524ebb-4494-47df-b258-d933c0248942 ...
error= workspace has no running agent: the workspace is likely stopped. Use the start_workspace tool to start it:
github.com/coder/coder/v2/coderd/x/chatd.init
<autogenerated>:1
```
"workspace agent not resolvable" is printed by
[`fetchContextForBuild`](<https://github.com/coder/coder/blob/fecc991ac9f9d673d7a772b0042ca821d19b6296/coderd/x/chatd/workspace_context_builder.go#L145>).
this causes
[`buildWorkspaceContext`](<https://github.com/coder/coder/blob/fecc991ac9f9d673d7a772b0042ca821d19b6296/coderd/x/chatd/workspace_context_builder.go#L60>)
to exit with a `errWorkspaceContextUnavailable` error. That in turn is
interpreted by
[`persistWorkspaceContext`](<https://github.com/coder/coder/blob/fecc991ac9f9d673d7a772b0042ca821d19b6296/coderd/x/chatd/generation.go#L838>)
as an "expected exit" scenario. That's a bug: because the task exits
without changing the chat state, the runner never issues another task to
process the chat any further. But even if it did, it'd go through the
same code path and exit again. We need to ensure that
`persistWorkspaceContext` commits a marker file even if it cannot reach
the agent.
Hugo Dutka
61a7b800e2