[nexxeln]

Stack: #49 ← #50

Why the change

A deleted .rift marker or an uninitialized parent showed up in OpenCode as raw errors like rift marker is missing: <path>, and the rift.remove tool didn't tell the agent which removals it refuses.

Special things to note

• Stacked on fix(opencode): report committed hook failures in tool results #49. Merge that first.
• The hints reuse the wording the CLI already prints in crates/cli/src/main.rs. Every other error keeps its original message.

Change outline

The one hard-coded rewrite becomes a table of error code to hint.

+hints = {
+  workspace_not_initialized: "Rift source is not initialized; run `rift init` from the project root first",
+  initialization_required:   "This Rift workspace must be initialized first; run `rift init` from its root folder",
+  missing_marker:            "This Rift workspace is missing its `.rift` marker; run `rift init` to restore it",
+}
 failure(error)
-  if code is workspace_not_initialized → hint, else error.message
+  hints[error.code] ?? error.message

Docs the agent and users see:

 rift.remove description
-  Remove a Rift workspace from the current project.
+  … Refuses the workspace this session is in and workspaces that still have child workspaces.

 plugins/opencode/README.md › Limits
+  Windows can't create workspaces, because Rift needs copy-on-write cloning.