Improve git commit message generation

[joaomoreno]

Related issues:

• Git Commit Message Doesn't Overwrite User Message
• Feature Request: Improve GitHub’s Auto-Generated Commit Messages
• Copilot is random when generating commit messages

A few ideas:

• Include summarized documents of the files affected by the changes, in the prompt
• Include latest refactorings made by the user

[isidorn]

Excited about this one and happy to provide feedback.

[ceolinwill]

It should also consider instructions added to .github/copilot-instructions.md.

Not sure if it takes time to index the instructions, but the commit message seems to ignore them completely.

Example:

1. Create a JavaScript file, declare a variable using let, and commit it.
2. Change the variable to use const instead.
3. Generate a commit message. Copilot will likely suggest something like:
   "Refactor: Change var declarations to const in app.js".
4. Add an instruction to copilot-instructions.md:
   "Avoid using 'Refactor:' as a prefix for commit messages."
5. Generate the message again.

The new instruction appears to be ignored.

Another option is to use a separate file for commit instructions. This would help keep general instructions separate from commit-specific ones.

[lszomoru]

Another option is to use a separate file for commit instructions. This would help keep general instructions separate from commit-specific ones.

@ceolinwill, you can use the github.copilot.chat.commitMessageGeneration.instructions setting to either specify the custom instructions or to specify a file from the workspace that contains the custom instructions. Please give it a try and let me know if that does not work as expected.

[lszomoru]

Starting with Copilot Chat version 0.26.2025031801 we are including the original document (summarized) as context. Tested some of the known scenarios and the additional context has helped improve the quality of the commit message.

[ceolinwill]

@lszomoru Thanks! The issue with github.copilot.chat.commitMessageGeneration.instructions is that it requires adding a .vscode/settings.json file to the repo, which isn’t ideal in my opinion.

It would be more intuitive if Copilot had a default instructions file for commits, like .github/commit-instructions.md. Even better, a .github/copilot directory could centralize all Copilot-related instructions, making it easier to manage:

• .github/copilot/commits.md
• .github/copilot/naming-conventions.md
• .github/copilot/i18n.md
  1 etc.

That might be a separate issue or feature request, though.

[lszomoru]

@ceolinwill, the github.copilot.chat.commitMessageGeneration.instructions setting follows the pattern for specifying custom instructions already established within the Copilot Chat extension. Please feel free to file a separate feature request for your suggestion.