Letta Configuration

Complete guide for configuring models on agents and providers on servers.

When to Use This Skill

Agent-level (model configuration):

Creating agents with specific model configurations
Adjusting model settings (temperature, max tokens, context window)
Configuring provider-specific features (OpenAI reasoning, Anthropic thinking)
Changing models on existing agents

Server-level (provider configuration):

Setting up BYOK (bring your own key) providers
Configuring self-hosted deployments with environment variables
Validating provider credentials
Setting up custom OpenAI-compatible endpoints

Not covered here: Model selection advice (which model to choose) - see agent-development skill.

Part 1: Model Configuration (Agent-Level)

Model Handles

Models use a provider/model-name format:

Provider	Handle Prefix	Example
OpenAI	`openai/`	`openai/gpt-4o`, `openai/gpt-4o-mini`
Anthropic	`anthropic/`	`anthropic/claude-sonnet-4-5-20250929`
Google AI	`google_ai/`	`google_ai/gemini-2.0-flash`
Azure OpenAI	`azure/`	`azure/gpt-4o`
AWS Bedrock	`bedrock/`	`bedrock/anthropic.claude-3-5-sonnet`
Groq	`groq/`	`groq/llama-3.3-70b-versatile`
Together	`together/`	`together/meta-llama/Llama-3-70b`
OpenRouter	`openrouter/`	`openrouter/anthropic/claude-3.5-sonnet`
Ollama (local)	`ollama/`	`ollama/llama3.2`

Basic Model Configuration

from letta_client import Letta

client = Letta(api_key="your-api-key")

agent = client.agents.create(
    model="openai/gpt-4o",
    model_settings={
        "provider_type": "openai",  # Required - must match model provider
        "temperature": 0.7,
        "max_output_tokens": 4096,
    },
    context_window_limit=128000
)

Common Settings

Setting	Type	Description
`provider_type`	string	Required. Must match model provider (`openai`, `anthropic`, `google_ai`, etc.)
`temperature`	float	Controls randomness (0.0-2.0). Lower = more deterministic.
`max_output_tokens`	int	Maximum tokens in the response.

Changing an Agent's Model

client.agents.update(
    agent_id=agent.id,
    model="anthropic/claude-sonnet-4-5-20250929",
    model_settings={"provider_type": "anthropic", "temperature": 0.5},
    context_window_limit=64000
)

Note: Agents retain memory and tools when changing models.

Provider-Specific Settings

For OpenAI reasoning models and Anthropic extended thinking, see references/provider-settings.md.

Part 2: Provider Configuration (Server-Level)

Quick Start

# Add provider via API
python scripts/setup_provider.py --type openai --api-key sk-...

# Generate .env for Docker
python scripts/generate_env.py --providers openai,anthropic,ollama

# Validate credentials
python scripts/validate_provider.py --provider-id provider-xxx

Add BYOK Provider

# Via REST API
curl -X POST http://localhost:8283/v1/providers \
  -H "Content-Type: application/json" \
  -d '{
    "name": "My OpenAI",
    "provider_type": "openai",
    "api_key": "sk-your-key-here"
  }'

Supported Provider Types

openai, anthropic, azure, google_ai, google_vertex, ollama, groq, deepseek, xai, together, mistral, cerebras, bedrock, vllm, sglang, hugging_face, lmstudio_openai

For detailed configuration of each provider, see:

references/common_providers.md - OpenAI, Anthropic, Azure, Google
references/self_hosted_providers.md - Ollama, vLLM, LM Studio
references/all_providers.md - Complete reference
references/environment_variables.md - Docker/self-hosted setup

Anti-Hallucination Checklist

Before configuring:

Model handle uses correct provider/model-name format
model_settings includes required provider_type field
context_window_limit is set at agent level, not in model_settings
Provider-specific settings use correct nested structure
For self-hosted: embedding model is specified
Temperature is within valid range (0.0-2.0)

Scripts

Model configuration:

scripts/basic_config.py - Basic model configuration
scripts/basic_config.ts - TypeScript equivalent
scripts/change_model.py - Changing models on existing agents
scripts/provider_specific.py - OpenAI reasoning, Anthropic thinking

Provider configuration:

scripts/setup_provider.py - Add providers via REST API
scripts/validate_provider.py - Check provider credentials
scripts/generate_env.py - Generate .env for Docker

letta-configuration