Getting started

Quick start

If you have an API key set and know your provider, this is all you need:

# OpenAI
codriver::codriver_configure("openai", model = "gpt-5.1")

# Anthropic Claude
codriver::codriver_configure("anthropic", model = "claude-sonnet-4-5")

# OpenAI-compatible endpoint
codriver::codriver_configure("openai_compatible",
  base_url = "https://llmproxy.example.com/v1",
  model    = "gpt-4.1"
)

Any provider and argument supported by ellmer works. Read on if you need help with provider naming, authentication, or provider-specific notes.

Providers

Codriver does not communicate with LLM providers directly. Instead, it relies on ellmer, a package that provides a unified interface to a wide range of providers. Ellmer supports many popular services — OpenAI, Anthropic Claude, Google Gemini, Mistral, Ollama, and more — and handles the details of authentication and communication for each one.

When you call codriver::codriver_configure(), you tell codriver which provider to use by passing its name — a short string like "openai" or "anthropic". Any argument accepted by the corresponding ellmer constructors can be passed directly through codriver_configure().

The table covers providers commonly used. Ellmer supports additional providers - see the ellmer homepage for the full and current list.

Most providers require a model to be specified, but ellmer will select a default for most providers. If a default is used, ellmer will print it to the console on every codriver call. Specifying the model explicitly in codriver_configure() avoids this.

Authenticating

Before codriver can send requests to an LLM, it needs to prove to the provider that you are authorised to use it. How this works depends on the provider.

The most common approach is an API key: a secret string that you obtain from your provider’s website and store on your machine. Ellmer looks for these keys in environment variables — named slots in your R session that hold configuration values. Each provider expects its key in a specific variable.

The table above lists the environment variable names of commonly used providers. If your provider is not in the table or uses a different authentication mechanism, look at the help page for the corresponding ellmer constructor. For example, running ?ellmer::chat_openai in R will tell you that OpenAI expects OPENAI_API_KEY and ?ellmer::chat_aws_bedrock tells you about their specific authentication mechanism.

The recommended way to set an environment variable permanently is to add it to your .Renviron file, which R reads automatically at startup. The example below shows how this is done.

OpenAI

OpenAI is the provider codriver has been most thoroughly tested with. GPT-4.1 and GPT-5.1 both produce clean, reliable completions in the RStudio workflow codriver is designed for.

To get started, go to platform.openai.com, sign in, and create an API key under API keys.

Then store it in your .Renviron:

file.edit("~/.Renviron")

Add:

OPENAI_API_KEY=your_key_here

Save the file, restart R and then configure codriver:

codriver::codriver_configure("openai", model = "gpt-5.1")

That is all that is needed. You’re now ready to start using codriver in your RStudio workflow.

OpenAI-compatible endpoint

Many organisations run their own LLM infrastructure that speaks the OpenAI API format. This includes local model servers, research clusters, and company proxies. For these, use "openai_compatible" as the provider name.

Unlike named providers, an OpenAI-compatible endpoint has no defaults. You will need to know the base URL and model name from your organisation’s documentation or administrator.

By default, "openai_compatible" reads the API key from the environment variable OPENAI_API_KEY. If you want to keep it separate from an actual OpenAI key, save a different key under a custom environment variable name and pass it explicitly:

codriver::codriver_configure(
  "openai_compatible",
  base_url    = "https://llmproxy.example.com/v1",
  model       = "gpt-5.1",
  credentials = function() Sys.getenv("CUSTOM_API_KEY")
)

Note: older ellmer documentation may show an api_key argument - this is deprecated in favour of credentials in combination with an environment variable, which avoids hardcoding keys in your code.

Provider notes

Some notes on experience with providers:

• OpenAI is the provider codriver has been most thoroughly tested with. GPT-4.1 and GPT-5.1 both produce clean, reliable completions in the RStudio workflow codriver is designed for.

• Anthropic Claude models have also been tested quite extensively. Especially Claude Sonnet 4.5 has been confirmed to work well with codriver.

• Google Gemini produces good results too. When using free tier be aware that some models are very slow and only allow for a few requests per day. Gemini 3.1 Flash Lite has been proven to be quick and works well with codriver.

  The Gemini Flash 2.5 (non-lite) series models use an internal reasoning process that can occasionally cause thought text to appear in completions. If you encounter this, try passing api_args to suppress thought output in the response:

  codriver::codriver_configure(
    "google_gemini",
    model    = "gemini-2.5-flash",
    api_args = list(
      generationConfig = list(
        thinkingConfig = list(includeThoughts = FALSE)
      )
    )
  )

Next: Using codriver