custom instructions for copilot reviews

[angiejones]

Summary

Type of Change

• Feature
• Bug fix
• Refactor / Code quality
• Performance improvement
• Documentation
• Tests
• Security fix
• Build / Release
• Other (specify below)

AI Assistance

• This PR was created or reviewed with AI assistance

[Copilot]

Pull Request Overview

This PR adds comprehensive GitHub Copilot code review instructions to guide AI-assisted code reviews for the project.

• Establishes clear review philosophy emphasizing high-confidence feedback and actionable comments
• Defines priority areas including security, correctness, architecture patterns, and testing gaps
• Provides project-specific context for Rust workspace structure and tooling requirements

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💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[michaelneale]

looks good @angiejones where did you get those guidelines from?

I think over time if we see it flag things incorrectly which are due to specific quirks of how goose works vs other style of apps, we can easily add the tips to here.

I likeit.

[DOsinga]

thanks for doing this, we do need something here. I wonder though if we should just all go through the reviews we got from copilot and collect what was useful and what was not.

[DOsinga]

fwiw, the three comments I got on this:

#5643

were all spot on

[tlongwell-block]

This is a great idea. Something to keep in mind, copilot does read AGENTS.md in the root and in subdirectories. Though hard to tell if that is just the "coding" agent, or copilot in general, including the review bot.

(Maybe goose should check subdirs too when it is working. That would be a nice feature that would allow per-crate instructions, @DOsinga?)

So, we could probably reduce duplication a bit between the instructions file here and agents.

[DOsinga]

I actually have some notes on what goes often wrong in our code:

Do not make things optional that don't need to be. The compiler is annoying but is your friend
Remove useless LLM comments - at best they take up space, at worst they will be outdated soon and will confuse
Beware for Goose suggesting to check 3 different things. It is probably only one
Booleans should default to false and not be optional
Beware of the context manager that doesn't need context
Clean up your logging
Avoid overly defensive code

[tlongwell-block]

I actually have some notes on what goes often wrong in our code:

Do not make things optional that don't need to be. The compiler is annoying but is your friend Remove useless LLM comments - at best they take up space, at worst they will be outdated soon and will confuse Beware for Goose suggesting to check 3 different things. It is probably only one Booleans should default to false and not be optional Beware of the context manager that doesn't need context Clean up your logging Avoid overly defensive code

I would probably put this in AGENTS.md so all AI working on the repo will follow these guidelines?

Looks like copilot review does respect agents, too https://docs.github.com/en/copilot/concepts/agents/code-review#providing-instructions-for-copilot-code-reviews

[DOsinga]

it's a good point that we include AGENTS.md anyway, but I would still think repeating the important bits as explicit code review instructions (pay attention to optional things that shouldn't) wouldn't hurt

[angiejones]

it's a good point that we include AGENTS.md anyway, but I would still think repeating the important bits as explicit code review instructions (pay attention to optional things that shouldn't) wouldn't hurt

added coding guidelines to AGENTS.md and review guidelines to the copilot custom instructions
2ccc3a7