[BUG] Cowork allow_cowork_file_delete fails with "Could not find mount" on paths with accented characters (macOS NFD vs NFC)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

The mcp__cowork__allow_cowork_file_delete tool returns "Could not find mount for path: <path>" when the path contains an accented character (e.g., "ç" in "Dissertação"), even though the folder is correctly connected to Cowork and every other tool operates on it normally.

Likely root cause: macOS (APFS/HFS+) stores filenames in Unicode NFD (Normalization Form Decomposed) — "ç" is stored as "c" + combining cedilla (U+0327), two codepoints. Linux/Windows use NFC (composed), where "ç" is the single codepoint U+00E7. The tool appears to compare the requested path against its registered mount list using literal string equality, without normalizing both sides. When one side is in NFD and the other in NFC, the comparison fails and the tool reports "Could not find mount", even though the mount exists.

Evidence the mount really exists: in the same session, mcp__workspace__bash with mv/cp/cat/ls/find all work on the same path; Read/Edit/Write file tools also work. Only allow_cowork_file_delete fails, which isolates the issue to path-comparison logic in that specific tool.

What Should Happen?

allow_cowork_file_delete should grant delete permission for files inside any connected folder, regardless of Unicode normalization form of the path. Both the incoming path and the mount registry should be normalized to a common form (NFC is conventional) before comparison.

Error Messages/Logs

Could not find mount for path: /sessions/<session-id>/mnt/Dissertação Tese e Estilo/_test_write.txt. Make sure the path is within a mounted directory.

Steps to Reproduce

1. Connect a folder with an accented character in its name to Cowork. Example: ~/Documents/Claude/Projects/Dissertação Tese e Estilo/
2. In a Cowork session, ask Claude to delete a file inside that folder.
3. Claude calls mcp__cowork__allow_cowork_file_delete with the file path.
4. Tool returns: "Could not find mount for path: /sessions/<id>/mnt/Dissertação Tese e Estilo/<file>. Make sure the path is within a mounted directory."
5. Verify the mount actually exists by running, in the same session: mcp__workspace__bash with find /sessions/<id>/mnt -maxdepth 1 -type d -name "Dis*Tese*" — the folder is found and mv/cp/ls all work on its files.

The failure is reproducible 100% of the time on any folder whose path contains "ç", "ã", "é", "ô" or similar precomposed Latin characters when the folder lives on macOS.

Claude Model

None

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

Claude 1.5354.0 (9a9e3d) 2026-04-29T01:14:34.000Z

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Other

Additional Information

This bug is in Cowork mode of the Claude Desktop app, not in Claude Code CLI. The bug report template is shared with Claude Code, so some fields (Terminal/Shell, Claude Code Version) don't map perfectly.

Suggested fix: normalize both the incoming path and the mount registry to NFC before comparison. In Python: unicodedata.normalize('NFC', path). In Node/JS: String.prototype.normalize('NFC').

Workaround: none for end users on macOS with accented folder names. Bash rm via mcp__workspace__bash also fails because bash lacks delete permission — that permission is exactly what allow_cowork_file_delete was supposed to grant. Affected users currently have to delete files manually via Finder.

Reference: existing Cowork bug reports show the channel is appropriate (e.g. #49276 about auto-update wiping Cowork projects on macOS).