Merge branch 'claudedo/295d5d409c194ba28dbb95ab13630832'

src/ClaudeDo.Worker/External/ExternalMcpService.cs

@@ -1059,15 +1059,18 @@ public sealed class ExternalMcpService
 
     [McpServerTool, Description(
         "Check whether a task would merge cleanly before touching anything — `git merge-tree --write-tree`, so the " +
-        "working tree, index and HEAD are untouched. status is 'clean' or 'conflict' (conflictFiles lists where git " +
-        "would stop); behind counts commits on targetBranch not yet on this branch, which flags a stale branch even " +
-        "when the preview is clean. If the list has a verify command configured, a clean preview is additionally " +
-        "built/tested in a scratch worktree (still without touching the real working tree) — verifyExitCode 0 means " +
-        "it built clean, non-zero or -1 (timeout/failed to start) means it doesn't, with the tail of its output in " +
-        "verifyOutputTail; verifyExitCode stays null when no verify command is configured. isEmpty=true means the " +
-        "task's review range contributed nothing; check that flag rather than reading a small changedFileCount as " +
-        "empty. Throws if the task has neither an active worktree nor a handler commit range, or the list's working " +
-        "directory is missing from disk.")]
+        "working tree, index and HEAD are untouched. status is 'clean', 'conflict' (conflictFiles lists where git " +
+        "would stop), or 'untracked_collision' (conflictFiles lists a path the branch adds that already exists, " +
+        "untracked, in the target working directory — merge-tree can't see the working tree at all, so this is the " +
+        "only way to catch it before a real merge either refuses or, if that path became tracked in the meantime, " +
+        "silently overwrites it); behind counts commits on targetBranch not yet on this branch, which flags a stale " +
+        "branch even when the preview is clean. If the list has a verify command configured, a clean preview is " +
+        "additionally built/tested in a scratch worktree (still without touching the real working tree) — " +
+        "verifyExitCode 0 means it built clean, non-zero or -1 (timeout/failed to start) means it doesn't, with the " +
+        "tail of its output in verifyOutputTail; verifyExitCode stays null when no verify command is configured. " +
+        "isEmpty=true means the task's review range contributed nothing; check that flag rather than reading a " +
+        "small changedFileCount as empty. Throws if the task has neither an active worktree nor a handler commit " +
+        "range, or the list's working directory is missing from disk.")]
     public async Task<MergePreviewToolDto> PreviewMerge(
         string taskId,
         [Description("Branch to preview against; defaults to the repo's current branch.")]