---
title: API Reference
description: Complete reference for Llama Stack APIs
sidebar_label: Overview
sidebar_position: 1
---

# API Reference

Llama Stack provides a comprehensive set of APIs for building generative AI applications. All APIs follow OpenAI-compatible standards and can be used interchangeably across different providers.

## Core APIs

### Inference API
Run inference with Large Language Models (LLMs) and embedding models.

**Supported Providers:**
- Meta Reference (Single Node)
- Ollama (Single Node)
- Fireworks (Hosted)
- Together (Hosted)
- NVIDIA NIM (Hosted and Single Node)
- vLLM (Hosted and Single Node)
- TGI (Hosted and Single Node)
- AWS Bedrock (Hosted)
- Cerebras (Hosted)
- Groq (Hosted)
- SambaNova (Hosted)
- PyTorch ExecuTorch (On-device iOS, Android)
- OpenAI (Hosted)
- Anthropic (Hosted)
- Gemini (Hosted)
- WatsonX (Hosted)

### Agents API
Run multi-step agentic workflows with LLMs, including tool usage, memory (RAG), and complex reasoning.

**Supported Providers:**
- Meta Reference (Single Node)
- Fireworks (Hosted)
- Together (Hosted)
- PyTorch ExecuTorch (On-device iOS)

### Vector IO API
Perform operations on vector stores, including adding documents, searching, and deleting documents.

**Supported Providers:**
- FAISS (Single Node)
- SQLite-Vec (Single Node)
- Chroma (Hosted and Single Node)
- Milvus (Hosted and Single Node)
- Postgres (PGVector) (Hosted and Single Node)
- Weaviate (Hosted)
- Qdrant (Hosted and Single Node)

### Files API (OpenAI-compatible)
Manage file uploads, storage, and retrieval with OpenAI-compatible endpoints.

**Supported Providers:**
- Local Filesystem (Single Node)
- S3 (Hosted)

### Vector Store Files API (OpenAI-compatible)
Integrate file operations with vector stores for automatic document processing and search.

**Supported Providers:**
- FAISS (Single Node)
- SQLite-vec (Single Node)
- Milvus (Single Node)
- ChromaDB (Hosted and Single Node)
- Qdrant (Hosted and Single Node)
- Weaviate (Hosted)
- Postgres (PGVector) (Hosted and Single Node)

### Safety API
Apply safety policies to outputs at a systems level, not just model level.

**Supported Providers:**
- Llama Guard (Depends on Inference Provider)
- Prompt Guard (Single Node)
- Code Scanner (Single Node)
- AWS Bedrock (Hosted)

### Post Training API
Fine-tune models for specific use cases and domains.

**Supported Providers:**
- Meta Reference (Single Node)
- HuggingFace (Single Node)
- TorchTune (Single Node)
- NVIDIA NEMO (Hosted)

### Eval API
Generate outputs and perform scoring to evaluate system performance.

**Supported Providers:**
- Meta Reference (Single Node)
- NVIDIA NEMO (Hosted)

### Telemetry API
Collect telemetry data from the system for monitoring and observability.

**Supported Providers:**
- Meta Reference (Single Node)

### Tool Runtime API
Interact with various tools and protocols to extend LLM capabilities.

**Supported Providers:**
- Brave Search (Hosted)
- RAG Runtime (Single Node)

## API Compatibility

All Llama Stack APIs are designed to be OpenAI-compatible, allowing you to:
- Use existing OpenAI API clients and tools
- Migrate from OpenAI to other providers seamlessly
- Maintain consistent API contracts across different environments

## Getting Started

To get started with Llama Stack APIs:

1. **Choose a Distribution**: Select a pre-configured distribution that matches your environment
2. **Configure Providers**: Set up the providers you want to use for each API
3. **Start the Server**: Launch the Llama Stack server with your configuration
4. **Use the APIs**: Make requests to the API endpoints using your preferred client

For detailed setup instructions, see our [Getting Started Guide](../getting_started/quickstart).

## Provider Details

For complete provider compatibility and setup instructions, see our [Providers Documentation](../providers/).

## API Stability

Llama Stack APIs are organized by stability level:
- **[Stable APIs](./index.mdx)** - Production-ready APIs with full support
- **[Experimental APIs](../api-experimental/)** - APIs in development with limited support
- **[Deprecated APIs](../api-deprecated/)** - Legacy APIs being phased out

## OpenAI Integration

For specific OpenAI API compatibility features, see our [OpenAI Compatibility Guide](../api-openai/).