# Getting Started

Install CrabLLM, configure providers, and send your first request in under a minute.

## Install

```
cargo install crabllm
```

## Configure

Create a `crabllm.toml` file:

```
listen = "0.0.0.0:8080"

[providers.openai]
kind = "openai"
api_key = "${OPENAI_API_KEY}"
models = ["gpt-4o", "gpt-4o-mini"]

[providers.anthropic]
kind = "anthropic"
api_key = "${ANTHROPIC_API_KEY}"
models = ["claude-sonnet-4-20250514"]
```

Environment variables in `${VAR}` syntax are expanded at startup.

## Run

```
crabllm --config crabllm.toml
```

You'll see:

```
crabllm listening on 0.0.0.0:8080 (3 models, 2 providers, 0 extensions)
```

## Send a request

All requests use the OpenAI format, regardless of which provider handles them:

```
curl http://localhost:8080/v1/chat/completions \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-4o",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'
```

To use Anthropic, just change the model name:

```
curl http://localhost:8080/v1/chat/completions \
  -H "Content-Type: application/json" \
  -d '{
    "model": "claude-sonnet-4-20250514",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'
```

The request format is the same. CrabLLM translates it to the Anthropic Messages API internally.

## Streaming

Add "stream": true to get SSE streaming:

```
curl http://localhost:8080/v1/chat/completions \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-4o",
    "messages": [{"role": "user", "content": "Hello!"}],
    "stream": true
  }'
```

## Model aliasing

Map friendly names to canonical model names:

```
[aliases]
gpt4 = "gpt-4o"
claude = "claude-sonnet-4-20250514"
```

Now "model": "gpt4" routes to `gpt-4o`.

## What's next

- [Configuration](/content/docs/crabllm/configuration/index.html) — full reference for all config options
- [Providers](/content/docs/crabllm/providers/overview/index.html) — setup guides for each provider
- [Routing](/content/docs/crabllm/features/routing/index.html) — weighted routing, retry, and fallback

### On this page

- [Install](/content/docs/crabllm/getting-started#install/index.html) 
- [Configure](/content/docs/crabllm/getting-started#configure/index.html) 
- [Run](/content/docs/crabllm/getting-started#run/index.html)  
- [Send a request](/content/docs/crabllm/getting-started#send-a-request/index.html) 
- [Streaming](/content/docs/crabllm/getting-started#streaming/index.html) 
- [Model aliasing](/content/docs/crabllm/getting-started#model-aliasing/index.html) 
- [What's next](/content/docs/crabllm/getting-started#whats-next/index.html)