IntegrationDeveloper WorkflowVerified Last verified 2026-07-24

GitHub Copilot Extensions

by GitHub

Copilot Extensions let third-party tools and services plug into GitHub Copilot Chat. You install an extension from the GitHub Marketplace and invoke it in chat with an `@`-mention (for example `@github`); the extension's agent communicates with the Copilot platform over server-sent events and can call the GitHub API. Developers build extensions by creating and configuring a GitHub App backed by a deployed agent.

Official page

Works with

GitHub Copilot VS Code

Copilot Extensions, MCP servers, and agent skills.

When to use it

When you want a specific service (docs, monitoring, PM tool) available in Copilot Chat
Standardizing an internal tool as a Copilot extension for your org

When not to

For simple, local prompt tweaks — custom instructions are lighter weight

What it does

Invoke third-party agents inside Copilot Chat via `@extension`
Extend Copilot with external tools, services, and data
Build your own extension from a GitHub App plus a deployed agent

How to install

Setup steps with copy-paste config. Sources are cited under each method.

Install from the Marketplace

GitHub Copilot

Requires: GitHub Copilot enabled · A GitHub account with permission to install apps

1
Find an extension
Browse the Copilot Extensions section of the GitHub Marketplace and install one.
url
```
https://github.com/marketplace?type=apps&copilot_app=true
```
2
Invoke it in chat
Open Copilot Chat and `@`-mention the extension to route your request to it.
config
```
@github What are my open pull requests in this repo?
```

Building Copilot Extensions — documentation · GitHub · Documentation · accessed 2026-07-24

How to prompt it

Copy-paste prompts written to exercise this plugin, with what to expect.

Route a request to an extension

You installed an extension for your monitoring tool.

@your-extension Show the error rate for the checkout service over the last hour and link the noisiest trace.

What to expect: Copilot forwards the request to the extension's agent, which queries the service and returns the metrics and a link inside chat.

Extensions only see what their GitHub App is authorized for — review scopes on install.

Tips for getting the most out of it

Build extensions from the official example agents (such as Blackbeard) before wiring in real services.
An extension's agent must be deployed to an HTTP-reachable server and speak server-sent events to Copilot.

Prompts to pair with it

Real prompts from the IterPrompt library you can copy or run.

Prompt persona

4.8(123)

copilot

Turn any AI chat into a copilot with this community persona prompt.

1,881 copiesOpen ↗

Prompt programming

4.6(97)

Copilot

A community prompt for copilot, imported from LLM-Prompt-Library (MIT).

1,915 copiesOpen ↗

See more prompts in the library

Frequently asked questions

How do I build my own?+

Create and configure a GitHub App, connect it to a deployed agent that talks to the Copilot platform, and optionally list it on the Marketplace if it's public.

Do I need a Copilot subscription?+

Copilot Extensions run inside Copilot Chat, so Copilot access applies. Confirm current plan requirements on GitHub's pricing page — we don't publish unverified pricing.