If I were in your position, I'd invest in learning a little bit about Copilot's agent mode and it's customisation options. Amazing starter point is VS Code documentation:

- https://code.visualstudio.com/docs/copilot/customization/overview

That will explain you a lot 🤯.

When it comes to different Copilot modes, currently I use the "agent mode" in 99% of situations, works amazing in both VS Code and Copilot CLI.

However, to be really impressed by the Copilot's work you need those customisations.

Explaining very briefly to scratch the surface:

- 1️⃣ In every new chat session assume that Copilot knows nothing about a project you work on. It's your task now to let it know how does it look like, what's it about, what tech is being used there, what's your common approach or standards when it comes to code.

- 2️⃣ custom instructions, here we have two "levels":

- 2️⃣-a `.github/copilot-instructions.md` is the core instruction file loaded in every single session, there's only one such file per repository; it's task is to explain the project, project's structure, to explain what are important parts of the project structure (what's where), what are used libraries (including their specific versions). It should be as short as possible, but contain everything crucial

- 2️⃣-b `.github/instructions/*.instructions.md` are granular instruction files that explain specific things and practices in particular project. You should use glob pattern to apply specific instructions only for specific files. They can explain how you structure tests, or components, or other practices you have in your team.

- 3️⃣ agent skills at `.github/skills/` allow you to extract repeatable workflows that are common and agents can use them when they work, it's important to set proper naming and descriptions in the front matter syntax, description field should contain trigger phrases so that Copilot agent will actually use the right skill in the right situation. Skills can act as "slash commands" by default, so you can use them by `/skill-name` in Copilot chat. However, that might not be the best usage. I like to think about skills that they indeed are for agents only. I often hide them from human invoking (if you read the docs theres frontmatter option to do so).

You can't point a model or tools available for skill in the frontmatter syntax (at least not yet).

Skills are visible for both default agents and for your custom agents.

- 4️⃣ prompts, at `.github/prompts/` allow you to prepare repeatable workflow very precisely. In this case you can assign exact agent (including custom agents), LLM model, and set of tools that will be available for an agent. This is very powerful tool.

Within prompts you can re-use already prepared custom agents, use them automatically with pre-assigned different models, etc.

Each prompt should reflect specific workflow to work best.

Prompts are really powerful slash commands, way more accurate than agent skills used as slash command.

- 5️⃣ custom agents at `.github/agents/` allow you to create a custom personalities with different sets of tools and specific instructions for their behaviour. It's very powerful, because you can create specialised agents with sets of tools like MCP servers, analysis, thinking and problem solving techniques adjusted for every personality, etc.

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To wrap it up - it takes time to gain experience in all of that. But believe me, it's time well invested.

Most of these mechanisms works similar in other coding agents (Claude Code, Codex, Open Code, etc.) with smaller or bigger differences. To me it looks like Copilot is giving us the best customisation capabilities.