Integrate GitHub Copilot into Applications

This skill covers the GitHub Copilot SDK, which wraps the Copilot CLI via JSON-RPC to let applications programmatically interact with GitHub Copilot - session management, custom tools, hooks, MCP server integration, and streaming - across Node.js, Python, Go, and .NET. Prerequisites: GitHub Copilot CLI installed and authenticated, a Copilot subscription (Individual/Business/Enterprise, not required for BYOK), and Node.js 18+/Python 3.8+/Go 1.21+/.NET 8.0+.

Every language follows the same core pattern: create a client, create a session, send messages, then stop the client. Streaming responses are enabled by setting streaming: true on session creation and subscribing to assistant.message_delta events for real-time output, with an on(handler) method to subscribe to all events or a specific event type.

Custom tools let Copilot call application-defined functions - each defined with a name, description, JSON-schema parameters, and a handler - available per-language via defineTool (Node.js/Go) or a @define_tool decorator with Pydantic models (Python) or AIFunctionFactory.Create (.NET), then passed into session creation's tools array.

Hooks intercept session lifecycle points: onPreToolUse (before a tool executes, for permission control or argument modification, returning an allow/deny/ask decision with optional modified arguments or suppressed output), onPostToolUse (after execution, for result transformation or logging), onUserPromptSubmitted (message modification/filtering), onSessionStart/onSessionEnd (context setup/cleanup), and onErrorOccurred (custom error handling/retry).

MCP server integration connects pre-built tool capabilities via remote HTTP servers (type: "http" with a url) or local stdio servers (type: "local" with a command, args, and a tools allowlist or ["*"]), configurable with env, cwd, and timeout. Authentication resolves in priority order: an explicit githubToken in the constructor, environment variables (COPILOT_GITHUB_TOKEN then GH_TOKEN then GITHUB_TOKEN), stored OAuth from copilot auth login, or GitHub CLI credentials. BYOK (Bring Your Own Key) lets you use your own API keys without a Copilot subscription, configuring a provider (openai, azure, anthropic, or ollama) with baseUrl/apiKey/wireApi - using "responses" wire API for the GPT-5 series and "completions" for others.

Sessions persist across restarts via an explicit sessionId, resumable later with client.resumeSession() - though BYOK sessions must re-provide the provider config on resume since keys aren't persisted. infiniteSessions configuration (with backgroundCompactionThreshold and bufferExhaustionThreshold) handles long-running workflows that would otherwise exceed context limits. Additional session configuration covers custom agents (named personas with their own prompt), a systemMessage override, skillDirectories/disabledSkills for loading and disabling Copilot skills, and onPermissionRequest/onUserInputRequest handlers for programmatic tool permission and user-input responses. An external, separately-running CLI (copilot --headless --port 4321) can be connected to via cliUrl instead of letting the SDK auto-manage the process. Debugging is enabled via logLevel: "debug", with common issues covering CLI-not-found, authentication failures, using a session after destroy(), and connection-refused errors (mitigated by autoRestart).

import { CopilotClient } from "@github/copilot-sdk";

const client = new CopilotClient();
const session = await client.createSession({ model: "gpt-4.1" });

const response = await session.sendAndWait({ prompt: "What is 2 + 2?" });
console.log(response?.data.content);

await client.stop();

Use this skill when building applications that programmatically interact with GitHub Copilot - managing sessions, defining custom tools, hooking into session lifecycle events, integrating MCP servers, or streaming responses - in Node.js, Python, Go, or .NET.

Inputs: a prompt or task to send to a Copilot session, along with any custom tools, hooks, MCP server configs, or provider (BYOK) settings.

Outputs: a Copilot session response (streamed or awaited), tool-call results from custom or MCP-provided tools, and persisted/resumable session state.

@github/copilot-sdk (Node.js), github-copilot-sdk (Python), github.com/github/copilot-sdk/go (Go), GitHub.Copilot.SDK (.NET); GitHub Copilot CLI; Model Context Protocol servers; OpenAI, Azure OpenAI, Azure AI Foundry, Anthropic, and Ollama as BYOK providers.

Developers building applications that programmatically drive GitHub Copilot - custom tools, session hooks, MCP integrations, or BYOK model providers - across Node.js, Python, Go, or .NET.