agentlayer-provider-github-copilot

@humanlayer/agentlayer-provider-github-copilot

An AI SDK v3 (ProviderV3/LanguageModelV3) provider that talks to the GitHub Copilot chat API. It handles Copilot's device-code OAuth flow, injects the Copilot-specific auth/User-Agent/intent headers on every request, and routes each model to either the Chat Completions or Responses API. Auth tokens are persisted through the AuthStore interface from @humanlayer/agentlayer-provider-auth (file-backed by default).

Usage

import { createFileAuthStore } from '@humanlayer/agentlayer-provider-auth'
import { createCopilotProvider } from '@humanlayer/agentlayer-provider-github-copilot'
import { generateText } from 'ai'

const authStore = createFileAuthStore()
const copilot = createCopilotProvider({ authStore, version: 'my-agent' })

const result = await generateText({
	model: copilot.languageModel('gpt-4.1'),
	prompt: 'Say hello',
})

createCopilotProvider returns a ProviderV3 — only languageModel() is implemented; embeddingModel/imageModel/transcriptionModel/speechModel/rerankingModel throw NoSuchModelError. Use createCopilotLanguageModel({ authStore, modelId }) directly if you just need one model.

Auth (device code flow)

import { startDeviceOAuth } from '@humanlayer/agentlayer-provider-github-copilot'

const auth = await startDeviceOAuth({ store: authStore }) // pass enterpriseUrl for GHE
console.log(`Visit ${auth.url} and enter code ${auth.userCode}`)
const result = await auth.complete() // polls until the user approves

startDeviceOAuth uses the hardcoded COPILOT_CLIENT_ID and writes an OAuthAuthInfo (with enterpriseUrl if set) into the given AuthStore under COPILOT_PROVIDER_ID ("github-copilot"). Tokens have no real expiry (expiresAt: 0); the stored refreshToken (falling back to accessToken) is sent as the bearer token on every request.

Model discovery

import { listCopilotModels } from '@humanlayer/agentlayer-provider-github-copilot'

const models = await listCopilotModels({ authStore }) // CopilotModelMap keyed by model id

listCopilotModels hits GET /models, keeps only entries with model_picker_enabled and a non-disabled policy, and merges into an existing CopilotModelMap (pass existing to preserve locally-curated name/family/options overrides across refreshes).

Request flow

Every outbound request goes through a fetch wrapper (buildCopilotRequest) that resolves auth, rewrites the URL to the Copilot (or enterprise) base URL, and sets headers before calling the real fetch:

flowchart LR
    A["createCopilotLanguageModel"] -->|"gpt-5+ (not gpt-5-mini)"| B["sdk.responses()"]
    A -->|"other model ids"| C["sdk.chat()"]
    B --> D["fetch wrapper"]
    C --> D
    D --> E["resolveCopilotAuth(AuthStore)"]
    D --> F["buildCopilotHeaders"]
    F -->|"Authorization, User-Agent,\nOpenai-Intent, x-initiator,\nCopilot-Vision-Request"| G["GitHub Copilot API"]

Loading

shouldUseCopilotResponsesApi(modelId) picks the Responses API for gpt-5* models (excluding gpt-5-mini) and Chat Completions otherwise. buildCopilotHeaders also strips any caller-supplied Authorization/x-api-key headers, sets x-initiator to agent unless the last message is a real user turn (a synthetic SYNTHETIC_ATTACHMENT_PROMPT message does not count, so it still yields agent), and sets Copilot-Vision-Request: true when the request body contains an image part.

Key exports (src/index.ts)

• createCopilotProvider(options), createCopilotLanguageModel(options) — build the AI SDK provider/model.
• createCopilotSdk(options) / createCopilotSdkSettings(options) — lower-level access to the vendored OpenAI-compatible SDK (src/sdk/copilot).
• buildCopilotRequest, buildCopilotHeaders, resolveCopilotAuth — the auth/header plumbing, usable standalone.
• listCopilotModels, getCopilotModels, copilotModelsResponseSchema — model catalog fetch + zod schema.
• startDeviceOAuth, writeCopilotOAuthTokens, normalizeEnterpriseUrl, getCopilotApiBaseUrl, getCopilotOAuthUrls — OAuth device-code flow (src/copilot-oauth.ts).
• shouldUseCopilotResponsesApi, COPILOT_PROVIDER ("github-copilot"), COPILOT_PROVIDER_ID, SYNTHETIC_ATTACHMENT_PROMPT.
• Types: CopilotAuthInfo, CopilotProviderOptions, CopilotLanguageModelOptions, CopilotHeadersResult, CopilotModelDefinition, CopilotModelMap.

Notes

• src/sdk/copilot/** is a vendored/trimmed fork of the AI SDK's openai-compatible provider (chat + responses language models). Per its own README it exists only to support the Copilot provider — avoid pulling in unrelated changes there.
• Run tests with bun test from this directory (or bun run test from the repo root). test/copilot-real.test.ts is describe.skipped by default and only runs against a real Copilot auth file (~/.humanlayer/agent-sdk/auth.json or AGENTLAYER_AGENT_SDK_AUTH_PATH).