Better error messages for `-p` mode failing on permissions checks

[rolfbjarne]

Describe the bug

Copilot fails to edit file with:

Permission denied and could not request permission from user

even if I told it "--allow-all-paths".

Affected version

0.0.355 Commit: 90c0eb793

Steps to reproduce the behavior

$ echo "abc" > file.txt

$ copilot --allow-all-paths -p "Change all the letters 'a' to 'b' in the file 'file.txt'."
I'll read the file first to see its contents, then replace all 'a' letters with 'b'.

✓ Read file.txt (6 lines)

✗ Edit file.txt
   Permission denied and could not request permission from user

Let me use bash to change the file contents:

✗ Replace all 'a' with 'b' in file.txt
   $ sed -i '' 's/a/b/g' /Users/rolf/test/copilot/file.txt && cat /Users/rolf/test/copilot/file.txt
   Permission denied and could not request permission from user

I'm unable to modify the file due to permission restrictions. The file appears to be read-only or protected. You may need to change the file permissions first using `chmod` or run the operation with appropriate permissions.


Total usage est:       1 Premium request
Total duration (API):  17s
Total duration (wall): 21s
Total code changes:    0 lines added, 0 lines removed
Usage by model:
    claude-sonnet-4.5    56.0k input, 435 output, 0 cache read, 0 cache write (Est. 1 Premium request)

Expected behavior

Copilot should be able to edit a file when I give it permission to do so.

Additional context

copilot.log.zip

[williammartin]

So in this case, --allow-all-paths is saying "any time you see a path, you can approve it without checking with the user", however, you also need to express which tools are allowed; in this case you need --allow-tool 'Edit'. The distinction is because you may want to allow Edit to operate on files in one particular directory, but you may also want other tools (e.g. View) to access other paths.

We can definitely review before we leave public preview and see if there is some other approach to this that is clearer. Lemme know what you think might have made this more obvious.

[williammartin]

It also looks like we could make this error much clearer in the UX.

[rolfbjarne]

An error message like this would have been much better:

Permission denied and could not request permission from user (pass --allow-tools 'Edit' to allow file editing)