Summary

The SDK's TypeScript types include a provider configuration option in createSession() that suggests support for custom OpenAI-compatible providers (like Ollama), but the CLI completely ignores this configuration and always connects to GitHub's hosted models.

This prevents developers from:

• Using local Ollama models for privacy-sensitive code review
• Running the SDK in air-gapped/offline environments
• Avoiding API costs by using local models
• Testing with self-hosted model infrastructure

Expected Behavior

Based on the TypeScript types, this should work:

const session = await client.createSession({
    model: 'deepseek-coder-v2:16b',
    provider: {
        type: 'openai',
        baseUrl: 'http://localhost:11434/v1'  // Ollama endpoint
    },
    streaming: true
});

Expected: SDK connects to http://localhost:11434/v1 instead of GitHub's API.

Actual Behavior

The provider config is silently ignored:

1. Session creates successfully ✅
2. CLI always connects to GitHub's hosted API ❌
3. Local Ollama models are never called ❌
4. No error or warning that provider config was ignored ❌

Evidence / Investigation Results

1. TypeScript Types Suggest Feature Exists

Location: node_modules/@github/copilot-sdk/dist/index.d.ts

export interface SessionOptions {
    model: string;
    provider?: {
        type: 'openai';
        baseUrl: string;
        apiKey?: string;
    };
    streaming?: boolean;
    systemMessage?: string;
    tools?: Tool[];
}

The types clearly define provider as an optional parameter with baseUrl support.

2. CLI Ignores Provider Config

Test Code:

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

const client = new CopilotClient({
    logLevel: 'debug',
    cliPath: './node_modules/.bin/copilot'
});

// Ollama is running at localhost:11434
const session = await client.createSession({
    model: 'deepseek-coder-v2:16b',
    provider: {
        type: 'openai',
        baseUrl: 'http://localhost:11434/v1'  // Should use this
    },
    streaming: true
});

await session.send({ prompt: 'Say hello' });

Result:

✅ Session created
📨 Event: user.message
📨 Event: assistant.turn_start
📨 Event: session.usage_info
📨 Event: pending_messages.modified (repeats indefinitely)
⏰ Timeout after 30s (no response from Ollama)

Ollama Logs (running with ollama serve):

# Ollama receives NO requests from the SDK
# Confirmed with: ollama serve --debug
# Only sees health checks from curl, zero requests from Copilot CLI

3. Environment Variable Overrides Don't Work

Attempted various environment variables to force provider config:

# None of these work
export GITHUB_COPILOT_API_URL="http://localhost:11434/v1"
export COPILOT_API_URL="http://localhost:11434/v1"
export COPILOT_ENDPOINT="http://localhost:11434/v1"
export OPENAI_API_BASE="http://localhost:11434/v1"
export OPENAI_BASE_URL="http://localhost:11434/v1"

Result: All ignored, CLI still connects to GitHub.