Codespaces: Prevent Copilot from editing code/PRs?

[Sean-Hammond]

🏷️ Discussion Type

Question

💬 Feature/Topic Area

Copilot in GitHub

Body

In Codespaces specifically, how do I prevent Copilot from editing my code or making pull requests, across all Codespaces and repos, and keep it disabled unless I manually change the setting again? Sometimes, when I use the chat, it changes my code and prompts a PR without my consent. I have to include in every prompt "Do not change my code."

I'm not talking about inline suggestions (see my other question about that), but rather when Copilot actually changes the code.

[maheerCodes]

this one is a bit different from inline suggestions,,, what you're describing is Copilot's "agentic" / edit mode(sometimes called "Copilot Edits" or agent mode),where chat responses can directly modify files or open PRs rather than just suggesting text.this is a chat mode/feature, not really an "inline suggestion" setting, so its controlled differently .

the core issue,,,,chat mode selection.
copilot chat has different modes,,, typically something like "Ask", "Edit", and "Agent" (naming varies). "Ask" mode is purely conversational and shouldnt touch your files. "Edit"/"Agent" modes are the ones that can modify code directly. if your chat keeeps defaulting to an edit/agent mode, that's likely whats causing the unwanted changes.

• in the copilot chat panel, look for a mode dropdown/selector (often near the chat input box) ,,, set it to "Ask" mode explicitly,
• check if there's a default mode setting in your account-level copilot settings (github.com/settings/copilot) that controls which mode new chats open in ,,, if "Agent" or "Edit" is set as default,switching this to "Ask" should prevent new chats from starting in edit mode.

about PRs specifically .
if copilot is opening PRs on its own, this sounds like it might be using the "Copilot coding agent" feature, which is a more autonomous mode designed to take a task and produce a full PR.this is typically something thats explicitly invoked (e.g. assigning an issue to copilot, or a specific "delegate to copilot" action) rather thann something that happens from normal chat ,,so its worth checking if something in your workflow (extensions, keybindings, or accidentally clicking a "delegate" button) is triggering this without you realizing.

• check your org/repo settings if you're in an org ,,, admins can sometimes enable "copilot coding agent" org-wide, which might explain it appearing even when you didnt invoke it.
• as a workaround beyond the per-prompt instruction, some people create a custom chat instructions file (.github/copilot-instructions.md in the repo) with a standing instruction like "never edit files directly, only suggest changes" ,,,,, this applies repo-wide automatically without retyping it each time ,which might at least reduce the friction even if it doesnt fully solve the root setting.

honestly this is one of the newer/ fast-changing parts of copilot and the exact toggle names/locations have been shifting recently,,,,,,,,if the mode dropdown isnt visible in your chat panel version, it might be worth checking the copilot extension version in your codespace, older versions might not expose mode switching the same way.

hope the "Ask" mode default gets you most of the way there❤️❤️.

[Sean-Hammond]

Thank you, sir. I think this has happened in Ask mode, or maybe it switches to Agent mode without my control.

When I say PR, I mean after I use the chat, when it changes the code, it lets me accept or undo it, highlighting what it changed, similar to pull requests. Perhaps I am mistaken and this is not actually a PR, but it kind of looks like it (or rather maybe it is the editor from which I can make a PR if I want).

If I create an instructions.md, how do I keep it in Copilot's context? The chat by default does not include all files in its context, and I have to click on those manually for each prompt.

I'll try making sure I'm always in "Ask" mode and let you know if it works.

[maheerCodes]

good clarification ,,, what you're describing(chat changes code, shows a diff with accept/undo highlighting)is not a PR,,, thats "Copilot Edits" behavior,which is a separate inline-diff review UI in the editor itself, before anything ever touches github/PRs .so no actual PR is being created, just local file edits proposed with a diff view. good news is this means its purely an editor-side mode issue, nothing happening on github's side .

about "Ask" vs "Edit" confusingly looking similar.
if this happened while you thought you were in "Ask" mode,two possibilities,,, (1)copilot chat sometimes has a separate "Edit" tab / panel thats distinct from the main chat panel ,and it is easy to end up in the wrong one without realizing,especially if VS Code remembers the last-used panel when reopening. or (2)some versions of copilot chat let "Ask" mode itself propose edits via inline suggestions even without switching modes ,,, if so,the distinction might be more about which panel / view you're using(Chat sidebar vs inline Edit overlay)rather than a mode toggle within one panel .
worth checking,,,,,,,, when this happens ,is there a separate tab or icon at the top of the chat panel (often something like a pencil/ edit icon vs a chat bubble icon)?if so, those might be two entirely different entry points, and "Ask mode" within the chat bubble one might genuinely never edit files, while the pencil one always will, regardless of any internal "mode" setting.

about keeping copilot-instructions.md in context automatically .
good question ,,, the whole point of .github/copilot-instructions.md is that you dont need to manually attach it ,,,if the file exists at exactly that path (.github/copilot-instructions.md, in the repo root's .github folder), copilot chat is supposed to automatically include it as context for every chat in that workspace,without you clicking/attaching anything :

• double check the exact path and filename ,,it must be .github/copilot-instructions.md (not just copilot-instructions.md in the root, and not in .vscode/).
• there may be a setting controlling whether this auto-context is enabled ,,, in vscode settings, search for github.copilot.chat.codeGeneration.useInstructionFiles and make sure its true,
• if it still doesnt get picked up automatically, as a fallback you could put the same instruction at the very top of the file you're working in as a comment ,,, less elegant but guarantees its in context for that file specifically.

give the "Ask" mode test a shot first as you said, and if the instructions.md setting above isnt picked up automatically ,that combo (auto-loaded instructions + correct mode/panel)should hopefully cover it.

let i know how it goes........