Mateo Wang f028a622e2 fix(prometheus): emit litellm_remaining_tokens_metric for Bedrock and Vertex (#27705)
* fix(prometheus): emit remaining_tokens/requests gauges for bedrock + vertex (LIT-2719)

Bedrock and Vertex AI never return x-ratelimit-remaining-* response headers,
so litellm_remaining_tokens_metric / litellm_remaining_requests_metric only
fired for OpenAI / Azure / Anthropic deployments even when tpm/rpm was
configured on the router.

Add a provider-agnostic fallback in PrometheusLogger.async_log_success_event
that asks Router.get_remaining_model_group_usage() for the same model_group
and emits the gauges with configured_limit - current_usage when the upstream
provider didn't populate the headers itself. Existing OpenAI / Azure /
Anthropic flows are unchanged because the fallback short-circuits when both
header values are already present.

Tests: 8 new tests covering bedrock + vertex emission, header short-circuit,
partial-header fill, llm_router=None, missing model_group, empty router
result, and router exception swallowing.

Co-authored-by: Mateo Wang <mateo-berri@users.noreply.github.com>

* fix(prometheus): narrow except to ImportError, log router lookup failures via verbose_logger.exception

Address greptile review:
- The optional 'from litellm.proxy.proxy_server import llm_router' should
  guard against ImportError specifically, not all exceptions, so that
  unexpected errors (e.g. AttributeError from partially-initialized state)
  stay visible.
- get_remaining_model_group_usage failures are now logged via
  verbose_logger.exception (with traceback) instead of debug, matching the
  PR description's intent and avoiding silent loss of router-cache errors
  in production.

Co-authored-by: Mateo Wang <mateo-berri@users.noreply.github.com>

* fix(prometheus): subtract in-flight delta in router-remaining fallback

The router's TPM/RPM counter is incremented by
Router.deployment_callback_on_success, which fires alongside this
prometheus callback in the success-log fan-out. Prometheus wins the
race, so get_remaining_model_group_usage returns the pre-decrement
counter for the current request — while vendor headers
(OpenAI/Anthropic/Azure) are already post-decrement.

That broke parity between providers on the same gauge: dashboards
plotting litellm_remaining_requests_metric showed Bedrock/Vertex
perpetually one request behind Anthropic for the same throughput.

Replay the in-flight increment before emit: subtract total_tokens
from remaining_tokens and 1 from remaining_requests.

* Revert "fix(prometheus): subtract in-flight delta in router-remaining fallback"

This reverts commit 001ce95ecdd952b4b5a23dd2b1e62c4562c932bc.

* fix(router): post-decrement router-derived ratelimit headers

Router.set_response_headers injects x-ratelimit-remaining-{tokens,
requests} for providers that don't return them natively (Bedrock,
Vertex). The values come from get_remaining_model_group_usage, which
reads the router's TPM/RPM counter — incremented post-response by
deployment_callback_on_success. So the headers reflected the counter
state before the current request was counted: pre-decrement.

Vendor headers from OpenAI/Anthropic/Azure are post-decrement (the
vendor counted the request before responding). Same metric name, two
semantics — dashboards plotting litellm_remaining_requests_metric
showed Bedrock/Vertex perpetually one request behind for the same
throughput, and the HTTP response headers exposed the same skew to
clients.

Subtract the in-flight delta before writing: 1 from
remaining-requests, response.usage.total_tokens from remaining-tokens.
Fixes both the response headers and (transitively) the prometheus
gauges that read from standard_logging_payload.additional_headers.

---------

Co-authored-by: cursor <cursor@example.com>
Co-authored-by: Mateo Wang <mateo-berri@users.noreply.github.com>
2026-05-13 17:40:59 -07:00
2026-05-12 17:16:37 -07:00

🚅 LiteLLM

LiteLLM AI Gateway

Open Source AI Gateway for 100+ LLMs. Self-hosted. Enterprise-ready. Call any LLM in OpenAI format.

Deploy to Render Deploy on Railway

LiteLLM Proxy Server (AI Gateway) | Hosted Proxy | Enterprise Tier | Website

PyPI Version GitHub Stars Y Combinator W23 Whatsapp Discord Slack CodSpeed

Group 7154 (1)

What is LiteLLM

LiteLLM is an open source AI Gateway that gives you a single, unified interface to call 100+ LLM providers — OpenAI, Anthropic, Gemini, Bedrock, Azure, and more — using the OpenAI format.

Use it as a Python SDK for direct library integration, or deploy the AI Gateway (Proxy Server) as a centralized service for your team or organization.

Jump to LiteLLM Proxy (LLM Gateway) Docs
Jump to Supported LLM Providers


Why LiteLLM

Managing LLM calls across providers gets complicated fast — different SDKs, auth patterns, request formats, and error types for every model. LiteLLM removes that friction:

  • Unified API — one interface for 100+ LLMs, no provider-specific SDK juggling
  • Drop-in OpenAI compatibility — swap providers without rewriting your code
  • Production-ready gateway — virtual keys, spend tracking, guardrails, load balancing, and an admin dashboard out of the box
  • 8ms P95 latency at 1k RPS (benchmarks)

OSS Adopters

Stripe image Google ADK Greptile OpenHands

Netflix

OpenAI Agents SDK

Features

LLMs - Call 100+ LLMs (Python SDK + AI Gateway)

All Supported Endpoints - /chat/completions, /responses, /embeddings, /images, /audio, /batches, /rerank, /a2a, /messages and more.

Python SDK

uv add litellm
from litellm import completion
import os

os.environ["OPENAI_API_KEY"] = "your-openai-key"
os.environ["ANTHROPIC_API_KEY"] = "your-anthropic-key"

# OpenAI
response = completion(model="openai/gpt-4o", messages=[{"role": "user", "content": "Hello!"}])

# Anthropic  
response = completion(model="anthropic/claude-sonnet-4-20250514", messages=[{"role": "user", "content": "Hello!"}])

AI Gateway (Proxy Server)

Getting Started - E2E Tutorial - Setup virtual keys, make your first request

uv tool install 'litellm[proxy]'
litellm --model gpt-4o
import openai

client = openai.OpenAI(api_key="anything", base_url="http://0.0.0.0:4000")
response = client.chat.completions.create(
    model="gpt-4o",
    messages=[{"role": "user", "content": "Hello!"}]
)

Docs: LLM Providers

Agents - Invoke A2A Agents (Python SDK + AI Gateway)

Supported Providers - LangGraph, Vertex AI Agent Engine, Azure AI Foundry, Bedrock AgentCore, Pydantic AI

Python SDK - A2A Protocol

from litellm.a2a_protocol import A2AClient
from a2a.types import SendMessageRequest, MessageSendParams
from uuid import uuid4

client = A2AClient(base_url="http://localhost:10001")

request = SendMessageRequest(
    id=str(uuid4()),
    params=MessageSendParams(
        message={
            "role": "user",
            "parts": [{"kind": "text", "text": "Hello!"}],
            "messageId": uuid4().hex,
        }
    )
)
response = await client.send_message(request)

AI Gateway (Proxy Server)

Step 1. Add your Agent to the AI Gateway

Step 2. Call Agent via A2A SDK

from a2a.client import A2ACardResolver, A2AClient
from a2a.types import MessageSendParams, SendMessageRequest
from uuid import uuid4
import httpx

base_url = "http://localhost:4000/a2a/my-agent"  # LiteLLM proxy + agent name
headers = {"Authorization": "Bearer sk-1234"}    # LiteLLM Virtual Key

async with httpx.AsyncClient(headers=headers) as httpx_client:
    resolver = A2ACardResolver(httpx_client=httpx_client, base_url=base_url)
    agent_card = await resolver.get_agent_card()
    client = A2AClient(httpx_client=httpx_client, agent_card=agent_card)

    request = SendMessageRequest(
        id=str(uuid4()),
        params=MessageSendParams(
            message={
                "role": "user",
                "parts": [{"kind": "text", "text": "Hello!"}],
                "messageId": uuid4().hex,
            }
        )
    )
    response = await client.send_message(request)

Docs: A2A Agent Gateway

MCP Tools - Connect MCP servers to any LLM (Python SDK + AI Gateway)

Python SDK - MCP Bridge

from mcp import ClientSession, StdioServerParameters
from mcp.client.stdio import stdio_client
from litellm import experimental_mcp_client
import litellm

server_params = StdioServerParameters(command="python", args=["mcp_server.py"])

async with stdio_client(server_params) as (read, write):
    async with ClientSession(read, write) as session:
        await session.initialize()

        # Load MCP tools in OpenAI format
        tools = await experimental_mcp_client.load_mcp_tools(session=session, format="openai")

        # Use with any LiteLLM model
        response = await litellm.acompletion(
            model="gpt-4o",
            messages=[{"role": "user", "content": "What's 3 + 5?"}],
            tools=tools
        )

AI Gateway - MCP Gateway

Step 1. Add your MCP Server to the AI Gateway

Step 2. Call MCP tools via /chat/completions

curl -X POST 'http://0.0.0.0:4000/v1/chat/completions' \
  -H 'Authorization: Bearer sk-1234' \
  -H 'Content-Type: application/json' \
  -d '{
    "model": "gpt-4o",
    "messages": [{"role": "user", "content": "Summarize the latest open PR"}],
    "tools": [{
      "type": "mcp",
      "server_url": "litellm_proxy/mcp/github",
      "server_label": "github_mcp",
      "require_approval": "never"
    }]
  }'

Use with Cursor IDE

{
  "mcpServers": {
    "LiteLLM": {
      "url": "http://localhost:4000/mcp/",
      "headers": {
        "x-litellm-api-key": "Bearer sk-1234"
      }
    }
  }
}

Docs: MCP Gateway

Supported Providers (Website Supported Models | Docs)

Provider /chat/completions /messages /responses /embeddings /image/generations /audio/transcriptions /audio/speech /moderations /batches /rerank
Abliteration (abliteration)
AI/ML API (aiml)
AI21 (ai21)
AI21 Chat (ai21_chat)
Aleph Alpha
Amazon Nova
Anthropic (anthropic)
Anthropic Text (anthropic_text)
Anyscale
AssemblyAI (assemblyai)
Auto Router (auto_router)
AWS - Bedrock (bedrock)
AWS - Sagemaker (sagemaker)
Azure (azure)
Azure AI (azure_ai)
Azure Text (azure_text)
Baseten (baseten)
Bytez (bytez)
Cerebras (cerebras)
Clarifai (clarifai)
Cloudflare AI Workers (cloudflare)
Codestral (codestral)
Cohere (cohere)
Cohere Chat (cohere_chat)
CometAPI (cometapi)
CompactifAI (compactifai)
Custom (custom)
Custom OpenAI (custom_openai)
Dashscope (dashscope)
Databricks (databricks)
DataRobot (datarobot)
Deepgram (deepgram)
DeepInfra (deepinfra)
Deepseek (deepseek)
ElevenLabs (elevenlabs)
Empower (empower)
Fal AI (fal_ai)
Featherless AI (featherless_ai)
Fireworks AI (fireworks_ai)
FriendliAI (friendliai)
Galadriel (galadriel)
GitHub Copilot (github_copilot)
GitHub Models (github)
Google - PaLM
Google - Vertex AI (vertex_ai)
Google AI Studio - Gemini (gemini)
GradientAI (gradient_ai)
Groq AI (groq)
Heroku (heroku)
Hosted VLLM (hosted_vllm)
Huggingface (huggingface)
Hyperbolic (hyperbolic)
IBM - Watsonx.ai (watsonx)
Infinity (infinity)
Jina AI (jina_ai)
Lambda AI (lambda_ai)
Lemonade (lemonade)
LiteLLM Proxy (litellm_proxy)
Llamafile (llamafile)
LM Studio (lm_studio)
Maritalk (maritalk)
Meta - Llama API (meta_llama)
Mistral AI API (mistral)
Moonshot (moonshot)
Morph (morph)
Nebius AI Studio (nebius)
NLP Cloud (nlp_cloud)
Novita AI (novita)
Nscale (nscale)
Nvidia NIM (nvidia_nim)
OCI (oci)
Ollama (ollama)
Ollama Chat (ollama_chat)
Oobabooga (oobabooga)
OpenAI (openai)
OpenAI-like (openai_like)
OpenRouter (openrouter)
OVHCloud AI Endpoints (ovhcloud)
Perplexity AI (perplexity)
Petals (petals)
Predibase (predibase)
Recraft (recraft)
Replicate (replicate)
Sagemaker Chat (sagemaker_chat)
Sambanova (sambanova)
Snowflake (snowflake)
Text Completion Codestral (text-completion-codestral)
Text Completion OpenAI (text-completion-openai)
Together AI (together_ai)
Topaz (topaz)
Triton (triton)
V0 (v0)
Vercel AI Gateway (vercel_ai_gateway)
VLLM (vllm)
Volcengine (volcengine)
Voyage AI (voyage)
WandB Inference (wandb)
Watsonx Text (watsonx_text)
xAI (xai)
Xinference (xinference)

Read the Docs


Get Started

You can use LiteLLM through either the Proxy Server or Python SDK. Both give you a unified interface to access multiple LLMs (100+ LLMs). Choose the option that best fits your needs:

LiteLLM AI Gateway LiteLLM Python SDK
Use Case Central service (LLM Gateway) to access multiple LLMs Use LiteLLM directly in your Python code
Who Uses It? Gen AI Enablement / ML Platform Teams Developers building LLM projects
Key Features Centralized API gateway with authentication and authorization, multi-tenant cost tracking and spend management per project/user, per-project customization (logging, guardrails, caching), virtual keys for secure access control, admin dashboard UI for monitoring and management Direct Python library integration in your codebase, Router with retry/fallback logic across multiple deployments (e.g. Azure/OpenAI) - Router, application-level load balancing and cost tracking, exception handling with OpenAI-compatible errors, observability callbacks (Lunary, MLflow, Langfuse, etc.)

Stable Release: Use docker images with the -stable tag. These have undergone 12 hour load tests, before being published. More information about the release cycle here

Support for more providers. Missing a provider or LLM Platform, raise a feature request.

Run in Developer Mode

Services

  1. Setup .env file in root
  2. Run dependant services docker-compose up db prometheus

Backend

  1. (In root) create virtual environment python -m venv .venv
  2. Activate virtual environment source .venv/bin/activate
  3. Install dependencies uv sync --all-extras --group proxy-dev
  4. uv run prisma generate
  5. prisma generate
  6. Start proxy backend python litellm/proxy/proxy_cli.py

Frontend

  1. Navigate to ui/litellm-dashboard
  2. Install dependencies npm install
  3. Run npm run dev to start the dashboard

Verify Docker Image Signatures

All LiteLLM Docker images published to GHCR are signed with cosign. Every release is signed with the same key introduced in commit 0112e53.

Verify using the pinned commit hash (recommended):

A commit hash is cryptographically immutable, so this is the strongest way to ensure you are using the original signing key:

cosign verify \
  --key https://raw.githubusercontent.com/BerriAI/litellm/0112e53046018d726492c814b3644b7d376029d0/cosign.pub \
  ghcr.io/berriai/litellm:<release-tag>

Verify using a release tag (convenience):

Tags are protected in this repository and resolve to the same key. This option is easier to read but relies on tag protection rules:

cosign verify \
  --key https://raw.githubusercontent.com/BerriAI/litellm/<release-tag>/cosign.pub \
  ghcr.io/berriai/litellm:<release-tag>

Replace <release-tag> with the version you are deploying (e.g. v1.83.0-stable).


Enterprise

For companies that need better security, user management and professional support

Get an Enterprise License Talk to founders

This covers:

  • Features under the LiteLLM Commercial License:
  • Feature Prioritization
  • Custom Integrations
  • Professional Support - Dedicated discord + slack
  • Custom SLAs
  • Secure access with Single Sign-On

Contributing

We welcome contributions to LiteLLM! Whether you're fixing bugs, adding features, or improving documentation, we appreciate your help.

Quick Start for Contributors

This requires uv to be installed.

git clone https://github.com/BerriAI/litellm.git
cd litellm
make install-dev    # Install development dependencies
make format         # Format your code
make lint           # Run all linting checks
make test-unit      # Run unit tests
make format-check   # Check formatting only

For detailed contributing guidelines, see CONTRIBUTING.md.

📖 Contributing to documentation? The LiteLLM docs have moved to a separate repository: BerriAI/litellm-docs. Please open doc PRs there. Docs are served at docs.litellm.ai.

Code Quality / Linting

LiteLLM follows the Google Python Style Guide.

Our automated checks include:

  • Black for code formatting
  • Ruff for linting and code quality
  • MyPy for type checking
  • Circular import detection
  • Import safety checks

All these checks must pass before your PR can be merged.

Support / talk with founders

Contributors

S
Description
Python SDK, Proxy Server (AI Gateway) to call 100+ LLM APIs in OpenAI (or native) format, with cost tracking, guardrails, loadbalancing and logging. [Bedrock, Azure, OpenAI, VertexAI, Cohere, Anthropic, Sagemaker, HuggingFace, VLLM, NVIDIA NIM]
Readme MIT 1.1 GiB
Languages
Python 81%
TypeScript 12.2%
JavaScript 5.9%
HTML 0.5%
HCL 0.2%