Providers Configuration

March 10, 2026 · View on GitHub

How to configure the providers that exist in the current codebase.

URL Constants

mcpplibs::llmapi::URL exposes common base URLs:

import mcpplibs.llmapi;
using namespace mcpplibs::llmapi;

URL::OpenAI
URL::Anthropic
URL::DeepSeek
URL::OpenRouter
URL::Poe

OpenAI

Use openai::OpenAI for OpenAI chat, streaming, tool calls, and embeddings.

auto client = Client(Config{
    .apiKey = std::getenv("OPENAI_API_KEY"),
    .model = "gpt-4o-mini",
});

Get keys from OpenAI Platform
Set OPENAI_API_KEY

Anthropic

Use anthropic::Anthropic for Anthropic chat and streaming.

auto client = Client(anthropic::Anthropic({
    .apiKey = std::getenv("ANTHROPIC_API_KEY"),
    .model = "claude-sonnet-4-20250514",
}));

Get keys from Anthropic Console
Set ANTHROPIC_API_KEY

OpenAI-Compatible Endpoints

The OpenAI provider accepts a custom baseUrl, so DeepSeek, OpenRouter, Poe, local gateways, and self-hosted OpenAI-compatible services can all reuse openai::OpenAI.

auto client = Client(openai::OpenAI({
    .apiKey = std::getenv("DEEPSEEK_API_KEY"),
    .baseUrl = std::string(URL::DeepSeek),
    .model = "deepseek-chat",
}));

You can also use a literal endpoint:

auto client = Client(openai::OpenAI({
    .apiKey = std::getenv("OPENROUTER_API_KEY"),
    .baseUrl = "https://openrouter.ai/api/v1",
    .model = "openai/gpt-4o-mini",
}));

Custom Headers And Proxy

auto provider = openai::OpenAI({
    .apiKey = std::getenv("OPENAI_API_KEY"),
    .baseUrl = std::string(URL::OpenAI),
    .model = "gpt-4o-mini",
    .proxy = "http://127.0.0.1:7890",
    .customHeaders = {
        {"X-Trace-Id", "demo-request"},
    },
});

Environment Variables

Typical setup:

export OPENAI_API_KEY="sk-..."
export ANTHROPIC_API_KEY="sk-ant-..."
export DEEPSEEK_API_KEY="..."
export OPENROUTER_API_KEY="..."

Provider Capabilities

Provider	Chat	Streaming	Embeddings	Notes
`openai::OpenAI`	yes	yes	yes	Also works with compatible endpoints
`anthropic::Anthropic`	yes	yes	no	Anthropic Messages API

Troubleshooting

Connection Issues

try {
    auto resp = client.chat("test");
} catch (const std::runtime_error& e) {
    std::cerr << "Network error: " << e.what() << '\n';
}

Authentication Errors

auto key = std::getenv("OPENAI_API_KEY");
if (!key || std::string(key).empty()) {
    std::cerr << "OPENAI_API_KEY not set\n";
}

Model Not Found

auto openaiClient = Client(openai::OpenAI({
    .apiKey = std::getenv("OPENAI_API_KEY"),
    .model = "gpt-4o-mini",
}));

auto anthropicClient = Client(anthropic::Anthropic({
    .apiKey = std::getenv("ANTHROPIC_API_KEY"),
    .model = "claude-sonnet-4-20250514",
}));