Today we're open sourcing a technical preview of the GitHub Copilot CLI SDK. Build agents with custom tools in Go, Python, TypeScript, and C#. Built on the same agent loop that powers the Copilot CLI and GitHub Coding Agent. Supports BYOK, and any model. Here is the Copilot CLI... driving Excel:show more

In the last few weeks, we've onboarded dozens of teams across Microsoft and GitHub onto the new GitHub Copilot CLI SDK. Expect to see many new agentic products ship in the coming weeks. Looking forward to collaborating with the community and hearing your feedback!

Can you only use it with a fine grained PAT or are there scopes we can add to OAuth login to access it? I have a GitHub OAuth provider in AGiXT that would be great to reuse to add an "Ask GitHub Copilot" ability without users having to do anything but reauthenticate.

We are working on org-scoped fine-grained PATs for higher rate limits, especially for automation/CI scenarios. More news on this soon!

Daaaaamn this is 🔥🔥🔥

I'm actually interested in trying the Excel integration of GitHub Copilot, is that some internal demo using this new Copilot SDK or is this already available somewhere I can just download and install it?

This is awesome. Open-sourcing the Copilot CLI SDK and supporting any model opens up so many possibilities for custom

Opening up the same agent loop behind Copilot and letting teams bring their own models and tools makes this far more than a demo. The ability to wire agents into real workflows like Excel is where this starts to feel genuinely useful in production.

I assume this requires Copilot CLI to be installed separately? I'm interested in integrating GitHub Copilot inside Remote Desktop Manager (.NET) for our built-in AI assistant which supports API keys from multiple AI providers, but I'd like a "login with GitHub Copilot" option

For node it is automatically included as an NPM dependency, for other languages we expect that there is a `copilot` on the PATH.

@awakecoding Can I just include a version of the copilot CLI in my software, so I can use the Copilot CLI SDK in it? What's the license there, the CLI isn't open-source.

@_Evan_Boyle Copilot CLI is updated so frequently that you'd still be better off supporting a copy of it installed separately, but I have the same comment. A pure .NET SDK for Copilot without requiring Copilot CLI would be ideal in our case

@_Evan_Boyle Oh you're right. I didn't pay attention to it, but seems like almost daily updates. Maybe it's worth testing it again, just to compare it to my beloved Claude Code :D

@_Evan_Boyle Wait a few days at least, I checked it this week and custom slash commands aren't listable yet

@haefeledev Custom slash commands are coming soon! Porting the core coding agent loop to another language would be a pretty huge lift. Our architecture for the Copilot SDK is similar to what others like Codex and Claude have done in this space.

How to Create AI Agents with Custom Functions Using GitHub Copilot SDK

BYOM is really cool! I have lots of agents with OpenAI compatible API

agents everywhere! love seeing the loop open up. already dreaming up a python toolchain with a dash of chaos. thanks for sharing the keys to the playground!

Do you have an ACP framework in there?

Not in the SDK. In the CLI we do have a hidden —acp flag that we haven’t shipped yet. Still in development but feel free to give it a try.

@draginol Yes!! Cc @willmcgugan hoping this works so I can test things out with Toad!!!

@draginol @willmcgugan Happy to collaborate @willmcgugan!

@marlene_zw @draginol Likewise. Would love to try running it under Toad. Let me know if I can assist.

@marlene_zw @draginol Just sent and intro email to some folks on our side.

Does Copilot CLI support the automatic workspace indexing feature from VSCode? This is what I'm referring to:

It does not, but in our experience the grep and agentic search tools we ship that run locally work just as well!

@haefeledev automatic workspace indexing from VSCode is *the* killer feature you have over the competition. You don't want good enough for Copilot CLI, you want the best which you already have in your other tools. Your only true competition in that area is Cursor in my mind

@haefeledev May it be with Copilot CLI or OpenCode, GitHub Copilot is really in a position to capture a lot of Claude Code users only by leveraging the GitHub workspace indexing. Please port it, full thread here:

@haefeledev Appreciate the feedback. We will think on it!

This is great! Inspires me to build similar add-in now. Thank you for sharing.

sadly can't use with cheap max 20x tokens

Cool

@_Evan_Boyle, the open-sourced SDK should help developers integrate custom tools into their Copilot workflows much easier.

Too late in the game. You guys started co-pilot, had millions of users for VS Code. And Claude ate not just your breakfast, lunch and dinner but ate you guys for after dinner late night snack. Not gonna work.

Sooooo, I can technically create a "debug" mode into my app that could catch errors in both web/api layers and automatically resolve them as I browse it? I have some stupid ideas for this, fun times ahead 🙃

What can this do that Claude Code can't and/or synergies with it? Personally a useful thing would be copilot replacing my n8n and make running local models much faster plug & play. Build all my outward APIs in a secure way to tap into like a LastPass

You can bring your own API keys and use any LLM model/provider including local LLMs!

there should really be some secret sauce with copilot that goes root access others can't, you guys have a lot of advantages I'd imagine. When I read "copilot" I think "the killer AI assistant", not necessarily going straight after the crowding CLI space. I should want to plug copilot into all of my CLIs for some unique benefits and ease of access. Just thoughts

Looking forward to it, Thanks Guys

The excel add-in for GH Copilot in use, has that been open sourced too?

Looks cool! 👍

so it is application calling copilot. Instead of copilot calling application via MCP. Still can't wrap my head about usage. Any idea anyone?

It is an agent framework. You can build your own agents with custom tools and prompts. It runs on top of the agent loop that powers the GitHub Copilot CLI.

@satyanadella These agents can than be access by copilot and studio?

Amazing

Isn't GH Copilot a coding agent, can it (via SDK) be used for General Purpose work flow? (e.g. Gemini API)

Yes, and yes. It is a coding agent, but the SDK allows you to customize and extend tools, prompts and behavior. The demo above has custom tools for interacting with Office documents.