diff --git a/docs/orchestration-lifecycle.md b/docs/orchestration-lifecycle.md
index 3733790d..702865eb 100644
--- a/docs/orchestration-lifecycle.md
+++ b/docs/orchestration-lifecycle.md
@@ -292,8 +292,9 @@ Ownership decides when the tree stops:
 | --- | --- |
 | Switching which session is viewed | keeps running |
 | Forking a session | keeps running; the new session starts with none of them |
+| Starting a new session, or resuming another one | keeps running |
 | Reloading settings or extensions | keeps running |
-| The owning session is deleted, replaced, or resumed away | stopped |
+| The owning session is deleted | stopped |
 | The host exits | stopped |
 
 Stopping goes through three layers, from narrowest to widest:
diff --git a/packages/coding-agent/src/features/step.ts b/packages/coding-agent/src/features/step.ts
index 3fc0efb1..adf520ad 100644
--- a/packages/coding-agent/src/features/step.ts
+++ b/packages/coding-agent/src/features/step.ts
@@ -590,10 +590,10 @@ function publishBackgroundCommandStatus(ctx: ExtensionContext): () => void {
 /**
  * Release the background process trees one session owns.
  *
- * Called from `session_shutdown`, which fires only when the session is really going away: `/new`,
- * resume, a deleted session, and quit. A session switch or a fork reuses the same session object
- * and never reaches this handler, so a dev server the user is watching keeps running while they
- * look at another conversation. That is the intended difference between "not visible" and "closed".
+ * Called from `session_shutdown` when `reason === "quit"`. That handler also fires for `new`,
+ * `resume`, `fork` and `reload`, and those keep the trees running: the conversation that owns them
+ * is still on disk — and, in a multi-session host, still on screen — so stopping its dev server
+ * would look like a bug. Only a host that is exiting, or a session being deleted, ends the work.
  *
  * Failure is reported, not thrown: a session that cannot stop one tree must still finish shutting
  * down, and the host-exit sweep is the backstop.