Using instruction files with applyTo

[finfin]

https://code.visualstudio.com/docs/copilot/copilot-customization#_use-instructionsmd-files

To use an instructions file for a chat prompt, you can either:

In the Chat view, select Add Context > Instructions and select the instruction file from the Quick Pick.
Run the Chat: Attach Instructions command from the Command Palette (⇧⌘P) and select the instruction file from the Quick Pick.
Configure the applyTo property in the instruction file header to automatically apply the instructions to specific files or folders.

Custom instruction is wonderful. But if we have to manually add instruction to the context, the use of applyTo is somewhat limited. (Also, in current flow, I'm having hard time finding out which instruction is filtered out by applyTo )

What if we can combine 'applyTo' and settings.json for more automatic instruction selecting? Like

"github.copilot.chat.codeGeneration.instructions": [
...,
{
"file": ".github/instructions/**.md" // all instruction is used by default, filtered by applyTo
}
],

[aeschli]

There are currently several ways that custom instructions to be added:

1. files from the setting github.copilot.chat.codeGeneration.instructions. These are always added, the applyTo header is not relevant
2. The .github/copilot-instructions.md file: Always added (unless setting is disabled), the applyTo header is not relevant
3. all the instruction files that are located at the location(s) defined by chat.instructionsFilesLocations (default: .github/instructions). You create these with New Instructions File and manage with Attach Instructions Files. These instructions support the applyTo

The instructions files from 3. can either be manually attached or automatically attached.
They are automatically added based on the the applyTo
If you add them manually the applyTo has no relevance, there's no filtering on manually added instructions

So for what you suggest we already do, The setting is not needed for that. Just place your instructions in github/instructions and set applyTo

[finfin]

There are currently several ways that custom instructions to be added:

1. files from the setting github.copilot.chat.codeGeneration.instructions. These are always added, the applyTo header is not relevant
2. The .github/copilot-instructions.md file: Always added (unless setting is disabled), the applyTo header is not relevant
3. all the instruction files that are located at the location(s) defined by chat.instructionsFilesLocations (default: .github/instructions). You create these with New Instructions File and manage with Attach Instructions Files. These instructions support the applyTo

The instructions files from 3. can either be manually attached or automatically attached. They are automatically added based on the the applyTo If you add them manually the applyTo has no relevance, there's no filtering on manually added instructions

So for what you suggest we already do, The setting is not needed for that. Just place your instructions in github/instructions and set applyTo

Wonderful to know that. Seems I'm need to read the document more thoroughly.

But after some experiment I'm having trouble making method 3 to work.

1. I put some instruction file in .github/shared/instructions
2. configure setting.json as following

{

  "chat.instructionsFilesLocations": {
    ".github/instructions": true,
    ".github/shared/instructions": true
  },
  "github.copilot.chat.codeGeneration.useInstructionFiles": true,
  ...others
}

3. have two instructions:

.github/shared/instructions/angular-apps.instructions.md :

--
applyTo: "libs/**"
--
... libs instructions

.github/shared/instructions/angular-libs.instructions.md :

--
applyTo: "apps/**"
--
... apps instructions

4. when I run command on the file under both libs and apps they did not appear to use my custom instruction as reference

[brutuscat]

Same issue here. only the copilot-instructions.md is picked up automatically.

Version: 1.100.2
Commit: 848b80a
Date: 2025-05-14T21:47:40.416Z
Electron: 34.5.1
ElectronBuildId: 11369351
Chromium: 132.0.6834.210
Node.js: 20.19.0
V8: 13.2.152.41-electron.0
OS: Darwin arm64 24.5.0

I found that the custom instructions in the directory only work if I call the @workspace participant. Otherwise it will only take the copilot named ones.

[brutuscat]

I also want to add that according to the docs: https://code.visualstudio.com/docs/copilot/copilot-customization#_use-instructionsmd-files

there should be an "add instruction" command but there is none....

The @workspace cannot be recalled in agent mode neither...

[kubasejdak]

Same here. I defined custom instruction file .github/instructions/python.instructions.md with applyTo: "**/*.py" and it was not used automatically when Python files were edited. When I changed it to applyTo: "**" then it was, but then it beats the purpose of applyTo.

I'm using VSCode Insiders with prerelease version of copilot extension:

[markgoho]

yes!

as far as I can tell, only applyTo: '**' is properly being picked up....any other file glob is not working at all

[aeschli]

#250754 fixes apply patterns with comma (/*.ts,/.tsx) and apply patterns with folder segments that do not start with **: someFolder/**/*.ts