Declarative Providers

Declarative providers allow you to add support for new LLM providers without writing Rust code. Simply define the provider’s configuration in a JSON file.

What are Declarative Providers?

Declarative providers are JSON configuration files that define:

Provider metadata (name, description)
API endpoint configuration
Supported models and their capabilities
Authentication requirements
Protocol format (OpenAI-compatible, etc.)

Goose automatically loads these configurations and creates fully functional providers.

Configuration File Structure

Declarative providers are located in crates/goose/src/providers/declarative/.

Basic Structure

{
  "name": "provider_id",
  "engine": "openai",
  "display_name": "Provider Display Name",
  "description": "Brief description of the provider",
  "api_key_env": "PROVIDER_API_KEY",
  "base_url": "https://api.provider.com/v1/chat/completions",
  "models": [
    {
      "name": "model-name",
      "context_limit": 128000,
      "max_tokens": 4096
    }
  ],
  "supports_streaming": true
}

Field Reference

Required Fields

name (string)

Unique identifier for the provider
Used in configuration and CLI
Must be lowercase, alphanumeric with underscores

"name": "groq"

engine (string)

Protocol/format the provider uses
Currently supported: "openai"
Determines how requests are formatted

"engine": "openai"

display_name (string)

Human-readable name shown in UIs
Can include spaces and special characters

"display_name": "Groq (d)"

description (string)

Brief description of the provider
Shown in provider selection UIs

"description": "Fast inference with Groq hardware"

api_key_env (string)

Environment variable name for API key
Convention: PROVIDER_API_KEY format

"api_key_env": "GROQ_API_KEY"

base_url (string)

API endpoint URL
For OpenAI-compatible providers, include full path to chat completions

"base_url": "https://api.groq.com/openai/v1/chat/completions"

models (array)

List of supported models
See Model Configuration

supports_streaming (boolean)

Whether the provider supports streaming responses
Most modern providers support this

"supports_streaming": true

Model Configuration

Each model in the models array defines:

{
  "name": "model-identifier",
  "context_limit": 131072,
  "max_tokens": 32768,
  "input_token_cost": 0.0000025,
  "output_token_cost": 0.00001
}

Model Fields

name (string, required)

Model identifier used in API requests
Exact string the provider expects

context_limit (integer, required)

Maximum context window size in tokens
Used for context management

max_tokens (integer, required)

Maximum output tokens per request
Used to limit response length

input_token_cost (float, optional)

Cost per input token in USD
Used for cost estimation

output_token_cost (float, optional)

Cost per output token in USD
Used for cost estimation

Complete Examples

Groq Provider

{
  "name": "groq",
  "engine": "openai",
  "display_name": "Groq (d)",
  "description": "Fast inference with Groq hardware",
  "api_key_env": "GROQ_API_KEY",
  "base_url": "https://api.groq.com/openai/v1/chat/completions",
  "models": [
    {
      "name": "llama-3.3-70b-versatile",
      "context_limit": 131072,
      "max_tokens": 32768
    },
    {
      "name": "llama-3.1-8b-instant",
      "context_limit": 131072,
      "max_tokens": 131072
    },
    {
      "name": "qwen/qwen3-32b",
      "context_limit": 131072,
      "max_tokens": 40960
    }
  ],
  "supports_streaming": true
}

Mistral Provider

{
  "name": "mistral",
  "engine": "openai",
  "display_name": "Mistral AI (d)",
  "description": "Mistral AI models",
  "api_key_env": "MISTRAL_API_KEY",
  "base_url": "https://api.mistral.ai/v1/chat/completions",
  "models": [
    {
      "name": "mistral-large-latest",
      "context_limit": 131072,
      "max_tokens": 32768,
      "input_token_cost": 0.000002,
      "output_token_cost": 0.000006
    },
    {
      "name": "mistral-small-latest",
      "context_limit": 32768,
      "max_tokens": 8192,
      "input_token_cost": 0.0000002,
      "output_token_cost": 0.0000006
    },
    {
      "name": "codestral-latest",
      "context_limit": 32768,
      "max_tokens": 8192,
      "input_token_cost": 0.0000002,
      "output_token_cost": 0.0000006
    }
  ],
  "supports_streaming": true
}

DeepSeek Provider

{
  "name": "deepseek",
  "engine": "openai",
  "display_name": "DeepSeek (d)",
  "description": "DeepSeek AI models",
  "api_key_env": "DEEPSEEK_API_KEY",
  "base_url": "https://api.deepseek.com/v1/chat/completions",
  "models": [
    {
      "name": "deepseek-chat",
      "context_limit": 65536,
      "max_tokens": 8192,
      "input_token_cost": 0.00000014,
      "output_token_cost": 0.00000028
    },
    {
      "name": "deepseek-reasoner",
      "context_limit": 65536,
      "max_tokens": 8192,
      "input_token_cost": 0.00000055,
      "output_token_cost": 0.0000022
    }
  ],
  "supports_streaming": true
}

Local Model Provider

{
  "name": "lmstudio",
  "engine": "openai",
  "display_name": "LM Studio (d)",
  "description": "Local models via LM Studio",
  "api_key_env": "LMSTUDIO_API_KEY",
  "base_url": "http://localhost:1234/v1/chat/completions",
  "models": [
    {
      "name": "local-model",
      "context_limit": 8192,
      "max_tokens": 2048
    }
  ],
  "supports_streaming": true
}

Creating a New Declarative Provider

1. Create Configuration File

Create a new JSON file in crates/goose/src/providers/declarative/:

touch crates/goose/src/providers/declarative/myprovider.json

2. Define Configuration

{
  "name": "myprovider",
  "engine": "openai",
  "display_name": "My Provider",
  "description": "Custom LLM provider",
  "api_key_env": "MYPROVIDER_API_KEY",
  "base_url": "https://api.myprovider.com/v1/chat/completions",
  "models": [
    {
      "name": "my-model-1",
      "context_limit": 128000,
      "max_tokens": 4096
    }
  ],
  "supports_streaming": true
}

3. Rebuild Goose

The provider is automatically loaded at build time:

cargo build

4. Configure and Use

Set the API key:

export MYPROVIDER_API_KEY=your-api-key

Configure Goose:

goose configure --provider myprovider --model my-model-1

Start using:

goose session

OpenAI-Compatible APIs

Many providers offer OpenAI-compatible APIs. For these:

Set "engine": "openai"
Use the provider’s base URL
Ensure model names match what the provider expects

Examples:

Together AI
Fireworks AI
Anyscale Endpoints
Modal
Replicate (with OpenAI compatibility)

Advanced Configuration

Multiple Model Variants

Include all model variants with accurate limits:

"models": [
  {
    "name": "model-small",
    "context_limit": 8192,
    "max_tokens": 2048,
    "input_token_cost": 0.0000001,
    "output_token_cost": 0.0000002
  },
  {
    "name": "model-medium",
    "context_limit": 32768,
    "max_tokens": 4096,
    "input_token_cost": 0.0000005,
    "output_token_cost": 0.000001
  },
  {
    "name": "model-large",
    "context_limit": 131072,
    "max_tokens": 8192,
    "input_token_cost": 0.000002,
    "output_token_cost": 0.000004
  }
]

Special Model Naming

Some providers use prefixes or special characters:

"models": [
  {
    "name": "meta-llama/llama-4-maverick-17b-128e-instruct",
    "context_limit": 131072,
    "max_tokens": 8192
  },
  {
    "name": "openai/gpt-oss-120b",
    "context_limit": 131072,
    "max_tokens": 65536
  }
]

Cost Tracking

Include accurate pricing for cost estimation:

{
  "name": "gpt-4o",
  "context_limit": 128000,
  "max_tokens": 16384,
  "input_token_cost": 0.0000025,
  "output_token_cost": 0.00001
}

Costs are per token in USD. Goose will:

Track token usage
Estimate costs per request
Show cumulative costs

Validation

Testing Your Provider

After creating a declarative provider:

# Build
cargo build

# Test configuration
goose configure --provider myprovider

# Test basic completion
goose session
> Hello, can you hear me?

Common Issues

Provider not found

Ensure JSON file is in crates/goose/src/providers/declarative/
Rebuild: cargo build
Check provider name matches filename (without .json)

Authentication failed

Verify environment variable name matches api_key_env
Check API key is set: echo $MYPROVIDER_API_KEY
Ensure API key format is correct

Model not found

Verify model name exactly matches provider’s API
Check provider documentation for exact model identifiers

Context limit errors

Reduce context_limit if requests fail
Check provider’s actual model limits
Some providers report limits differently

Limitations

Declarative providers currently:

Only support OpenAI-compatible APIs
Cannot implement custom OAuth flows
Cannot handle complex authentication schemes
Cannot customize request/response transformation

For providers requiring these features, implement a custom provider.

Contributing Declarative Providers

To add a provider to Goose:

Create the JSON configuration file
Test thoroughly
Document model capabilities accurately
Submit a PR to the Goose repository
Include example usage in PR description

See Contributing Guide for details.

Existing Declarative Providers

Goose includes these declarative providers:

Groq - Fast inference
Mistral - Mistral AI models
DeepSeek - DeepSeek models
Cerebras - Cerebras inference
Moonshot - Moonshot AI
Kimi - Kimi models
LM Studio - Local model hosting
OVHcloud - OVHcloud AI endpoints

See crates/goose/src/providers/declarative/ for complete configurations.

Next Steps

Learn about OAuth Providers
Implement Custom Providers
Read about Provider Architecture

Contributing

Building Extensions

Provider Development

Declarative Providers

What are Declarative Providers?

Configuration File Structure

Basic Structure

Field Reference

Required Fields

Model Configuration

Model Fields

Complete Examples

Groq Provider

Mistral Provider

DeepSeek Provider

Local Model Provider

Creating a New Declarative Provider

1. Create Configuration File

2. Define Configuration

3. Rebuild Goose

4. Configure and Use

OpenAI-Compatible APIs

Advanced Configuration

Multiple Model Variants

Special Model Naming

Cost Tracking

Validation

Testing Your Provider

Common Issues

Limitations

Contributing Declarative Providers

Existing Declarative Providers

Next Steps

Build docs developers (and LLMs) love

Contributing

Building Extensions

Provider Development

​What are Declarative Providers?

​Configuration File Structure

​Basic Structure

​Field Reference

​Required Fields

​Model Configuration

​Model Fields

​Complete Examples

​Groq Provider

​Mistral Provider

​DeepSeek Provider

​Local Model Provider

​Creating a New Declarative Provider

​1. Create Configuration File

​2. Define Configuration

​3. Rebuild Goose

​4. Configure and Use

​OpenAI-Compatible APIs

​Advanced Configuration

​Multiple Model Variants

​Special Model Naming

​Cost Tracking

​Validation

​Testing Your Provider

​Common Issues

​Limitations

​Contributing Declarative Providers

​Existing Declarative Providers

​Next Steps

Build docs developers (and LLMs) love

What are Declarative Providers?

Configuration File Structure

Basic Structure

Field Reference

Required Fields

Model Configuration

Model Fields

Complete Examples

Groq Provider

Mistral Provider

DeepSeek Provider

Local Model Provider

Creating a New Declarative Provider

1. Create Configuration File

2. Define Configuration

3. Rebuild Goose

4. Configure and Use

OpenAI-Compatible APIs

Advanced Configuration

Multiple Model Variants

Special Model Naming

Cost Tracking

Validation

Testing Your Provider

Common Issues

Limitations

Contributing Declarative Providers

Existing Declarative Providers

Next Steps