Docs: a PATH-resolved launch on Windows runs through the npm shim (ProcessId, linger after a hard kill) #290

What

The default launch (no Command, so opencode is resolved from PATH) works on Windows against an npm-installed CLI. The SDK resolves the npm shim opencode.CMD and starts it through cmd.exe /d /s /c. Two things the guide does not say:

• OpenCodeServer.ProcessId is the cmd.exe host, not the server. The server is a grandchild, beside conhost.
• After the owning process is killed hard, the server outlives it until its stdin lease ends it: measured 0.0 s with no turn run, then 6.6 s and 9.3 s after a model turn.

The XML describes the mechanism, but the README and the guide, which both use the default launch, mention neither the delay nor what ProcessId identifies with a shim.

Also a nit: Command is non-nullable, so assigning null to mean "the default" raises CS8601; the default comes only from a fresh OpenCodeServerOptions.

Severity: minor. Found by the default-launch check on Windows (apps 01 and 02, global CLI 2.0.29).

Proposed

Document in the connection-modes guide, for a shim-resolved launch, what ProcessId identifies and how long the server can outlive an owner that was killed hard. Resolving an npm shim to its target executable would be an SDK-only change made for safety, and it would have to be weighed against the launcher's "resolve like a shell" contract. That is a separate decision and not part of this issue.

Source: internal DevEx evaluation of 0.9.0-preview.10, default-launch follow-up, 2026-10-14 (finding DX-24).