Respect the Working Tree

Problem

Copilot keeps a mental model of what files look like from its own edits during a session. When the user manually edits a file outside of Copilot's view (e.g., in the editor, via git operations, or by reverting a change), Copilot will try to "re-apply" its version of the change — effectively overwriting what the user intentionally did.

This creates a tug-of-war over the working tree and is frustrating for developers who want to collaborate on the code, not just accept AI output wholesale.

Context / Trigger Conditions

• User says "STOP", "don't change that", "I made that change myself", or "leave it"
• User manually edits a file that Copilot previously modified
• User asks "what's next?" and Copilot starts re-verifying previous changes instead of moving forward
• File content in the IDE context doesn't match what Copilot wrote in the last session (this is normal — sessions are stateless; the file on disk is always correct)
• Copilot notices a file looks "old" compared to its session memory

Solution

1. The working tree is always the source of truth. If a file doesn't match what Copilot wrote last session, assume the user changed it intentionally.

2. Never re-apply a change without being asked. If Copilot thinks a change is missing, it should ask: "I notice X doesn't have Y — did you intentionally revert that?" — not silently re-apply it.

3. Always read before editing. Use get_file to read the current file state before making any change. Never assume the file matches a prior session's output.

4. Move forward, not backward. When a user asks "what's next?", answer that question. Don't use it as a trigger to verify or re-do prior work.

5. Session memory ≠ file state. Copilot's memory of "what I wrote" is irrelevant once the session ends. The file on disk is what matters.

Verification

Ask yourself before any file edit:

• Did I just read this file with get_file?
• Is the user asking me to change this, or am I doing it because I think it should match my prior work?
• If the user's version differs from mine, did I ask them about it?

Example

Bad pattern:

User: "What's next?" Copilot: "Let me verify the #2566 changes are actually in the file before moving on..." [Re-reads file, sees user's version, re-applies its own version anyway]

Good pattern:

User: "What's next?" Copilot: "Next up is #2564 — Surveyor Name autocomplete. Here's what it needs..."

Bad pattern:

User: "STOP" Copilot: [Continues applying changes anyway on the next turn]

Good pattern:

User: "STOP" Copilot: "Stopped. Waiting for your instructions."

Notes

• This is especially important in long sessions where multiple back-and-forth edits have occurred. The user's last manual edit is intentional, not an error to correct.
• The user may revert Copilot changes deliberately (to test, to simplify, or because they preferred a different approach) — that is their right.
• Git commits are also the user's domain. Never stage or commit without explicit instruction. If changes are uncommitted, that is also intentional — do not push or commit them.

References

• Copilot instructions: .github/copilot-instructions.md

Activation History

• 2026-02-28: Session where Copilot re-applied PwDatePicker changes the user had already made manually, and re-verified #2567 changes the user had committed themselves.