adding-models

name	adding-models
description	Guide for adding new LLM models to Letta Code. Use when the user wants to add support for a new model, needs to know valid model handles, or wants to update the model configuration. Covers models.json configuration, CI test matrix, and handle validation.

Adding Models

This skill guides you through adding a new LLM model to Letta Code.

Quick Reference

Key files:

• src/models.json - Model definitions (required)
• .github/workflows/ci.yml - CI test matrix (optional)
• src/tools/manager.ts - Toolset detection logic (rarely needed)

Workflow

Step 1: Find Valid Model Handles

Query the Letta API to see available models:

curl -s https://api.letta.com/v1/models/ | jq '.[] | .handle'

Or filter by provider:

curl -s https://api.letta.com/v1/models/ | jq '.[] | select(.handle | startswith("google_ai/")) | .handle'

Common provider prefixes:

• anthropic/ - Claude models
• openai/ - GPT models
• google_ai/ - Gemini models
• google_vertex/ - Vertex AI
• openrouter/ - Various providers

Step 2: Add to models.json

Add an entry to src/models.json:

{
  "id": "model-shortname"