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Deepanshu Lulla 0580465384
feat(router): add per-deployment allowed_fails_policy and cooldown_time override support (#34416)
* feat(router): add per-deployment allowed_fails_policy and cooldown_time override support

Three bugs fixed in the router cooldown system: (1) deployment-level allowed_fails and
allowed_fails_policy in model_info now take precedence over router-level settings in
_should_cooldown_deployment; (2) failed fallback deployments now get evaluated for
cooldown via _trigger_cooldown_for_failed_deployment, bypassing the Logging dedup gate;
(3) DualCache promotes Redis cooldown entries using default 600s TTL instead of true
remaining cooldown time -- _corrected_active_cooldown now evicts expired entries and
corrects stale in-memory TTLs on backfill. Adds ServiceUnavailableError, BadGatewayError,
and NotFoundError fields to AllowedFailsPolicy and cooldown_time to LiteLLMParamsTypedDict.

* fix(router): gate fallback cooldown trigger on has_logged_async_failure; use only litellm_metadata for deployment ID

* fix(router): use X | Y union syntax to fix UP007 strict lint gate

* test(router_utils): add coverage for _trigger_cooldown_for_failed_deployment and has_logged_async_failure gate

* test(router_utils): cover deployment cooldown override and exception swallow paths

* fix(router): add InternalServerError/ServiceUnavailableError/BadGatewayError/NotFoundError to router-level get_allowed_fails_from_policy

* fix(router): format router.py and add router-level policy tests

* test(router): add CI-visible coverage for per-deployment cooldown policy

Tests for `_get_deployment_cooldown_policy`, `_resolve_allowed_fails_from_policy`,
and `_should_cooldown_based_on_deployment_policy` (cooldown_handlers.py), the
`_corrected_active_cooldown` branches in CooldownCache, and the four new
exception-type branches in `Router.get_allowed_fails_from_policy` (router.py) --
all in `tests/test_litellm/` which the enterprise-routing CI job runs.

* fix(router): use is not None guard for cooldown_time_override in should_cooldown_based_on_allowed_fails_policy

A cooldown_time_override of 0 was previously treated as falsy and silently
fell through to the router-level cooldown_time value. Switched to an explicit
is not None check so that zero is honored as a valid override.

Added a regression test covering the zero case.

* fix(router): honor has_logged_async_failure and metadata for fallback cooldown; support both model_info and litellm_params locations

Manual verification against a live proxy surfaced that the fallback-cooldown-gap
trigger never actually fired: the has_logged_async_failure check read a plain
attribute that Logging never sets (the real flag lives in model_call_details),
and the deployment_id lookup only trusted litellm_metadata, which regular chat
completions never populate (only batch/thread/file endpoints do). Router
overwrites model_info on whichever key is present before every attempt, so
metadata is equally authoritative there, not caller-controlled as previously
assumed. Also let allowed_fails/allowed_fails_policy/cooldown_time be set under
either model_info or litellm_params, each preferring its own canonical location.

* fix(router): fix ContentPolicyViolationError policy shadowing and partial-policy zero-threshold

Two bugs from Greptile review on PR #34416:

- ContentPolicyViolationError subclasses BadRequestError, so listing
  BadRequestError first in _EXCEPTION_POLICY_FIELDS made the isinstance
  check always match BadRequestError for content-policy errors, using the
  wrong allowed_fails threshold. Reordered so the subclass is checked first.

- A deployment with a partial allowed_fails_policy and no deployment-wide
  allowed_fails forced allowed_fails_override=0 for any exception type its
  policy didn't cover, cooling the deployment down on the first unrelated
  failure. Now defers to router-level behavior for uncovered exception
  types instead of forcing an immediate cooldown.

* fix(router): only trust a metadata/litellm_metadata bucket the router itself wrote deployment info into

veria-ai flagged that preferring litellm_metadata whenever present could pick up a
caller-supplied litellm_metadata.model_info.id (preserved via allow_client_pricing_override)
instead of the metadata bucket the router actually populated for a regular completion's
fallback attempt, naming an arbitrary "victim" deployment for cooldown.

Router._update_kwargs_with_deployment() always writes model_info and
deployment_model_name into the same bucket together. Only trust a bucket that
carries deployment_model_name alongside model_info, since that marker is only
ever set by the router itself, not by request-body metadata.

* test(router): add regression coverage for ContentPolicyViolationError policy shadowing

The subclass-ordering fix in commit 38fe4e4490 had no regression test.
Verified the new test fails on the pre-fix ordering (asserts 2, got 10)
before restoring the fix, and confirmed the same behavior through the full
_should_cooldown_deployment call path against a real Router instance.

* fix(router): let explicit allowed_fails_policy entries override the generic 4XX cooldown exclusion

_is_cooldown_required skips cooldown evaluation for any 4XX status outside
{429, 401, 408, 404} by default, since a generic client error is usually not
the deployment's fault. BadRequestError and ContentPolicyViolationError both
carry status 400, so their AllowedFailsPolicy fields (BadRequestErrorAllowedFails,
ContentPolicyViolationErrorAllowedFails, both router-level pre-existing and the
new deployment-level ones) were silently unreachable: an operator could set
them to any value with no effect, since _is_cooldown_required blocked cooldown
evaluation before that policy was ever consulted.

_should_run_cooldown_logic now also checks whether an explicit allowed_fails_policy
entry (deployment-level or router-level) covers the exception's type, and if so,
proceeds with cooldown evaluation regardless of the generic status-code exclusion.
The exclusion remains the default for exception types with no explicit policy.

Verified live against a mock-triggered ContentPolicyViolationError (config-level
mock_response, azure/gpt-4.1-mini deployment) with BadRequestErrorAllowedFails=100
and ContentPolicyViolationErrorAllowedFails=0 on the same deployment: it now cools
down after exactly one ContentPolicyViolationError instead of never cooling down.

* fix(router): use the router-stamped failed_deployment_id for fallback cooldown targeting

Greptile flagged a real gap in the metadata-bucket-based deployment lookup:
for a generic-API-call fallback, the router writes the current attempt into
litellm_metadata, but a stale "metadata" bucket carrying the same
deployment_model_name marker (from an earlier point) would be picked first,
cooling the wrong deployment.

Router already has a more robust, pre-existing mechanism for this exact
problem: _set_failed_deployment_id_on_exception stamps the failing
deployment's id directly onto the exception at the point of failure,
immune to metadata-bucket ambiguity since a caller can't influence it and
it doesn't depend on which bucket the current call type happens to use.
It just wasn't called from _ageneric_api_call_with_fallbacks_helper's
except block, unlike _completion/_acompletion.

Added the missing call there (matching the existing pattern exactly), and
changed _trigger_cooldown_for_failed_deployment to prefer
exception.failed_deployment_id when present, falling back to metadata-bucket
inspection only for call paths that don't stamp it yet.

Verified live: the standard fallback-cooldown-gap scenario (two bad-key
deployments in a fallback chain) still correctly cools down both the
originally-called and fallback deployment.

* fix(router): address human review on per-deployment cooldown overrides

Scope allowed_fails_policy override to deployment-level only (a router-level
policy predates this feature and must keep its existing behavior), exempt
advisor-orchestration failures from the fallback cooldown trigger, keep the
single-deployment model group protection intact against a generic
deployment-level allowed_fails, make cooldown_time precedence consistent
across resolution paths, fix a falsy-zero swallowing bug in the router-level
allowed_fails fallback, and make allowed_fails_policy resolution fall through
to the next matching exception type instead of stopping at the first unset
field.

Also restrict allowed_fails/allowed_fails_policy/cooldown_time to model_info:
litellm_params gets copied into the actual provider request, so a router-only
setting placed there would leak into that request.

* test(router): update test_cooldown_handlers.py for the deployment-policy signature change

Surfaced by the rebase: this mirrored test file (tests/test_litellm/ mirrors
litellm/) predates the router_unit_tests/ coverage added earlier in this PR and
was still calling _should_cooldown_based_on_deployment_policy with its old
4-argument signature and asserting the now-removed litellm_params cooldown_time
location.

* test(router): update test_fallback_event_handlers.py for model_info-only cooldown_time

Another mirrored test file surfaced by the rebase that still asserted the
now-removed litellm_params.cooldown_time location.

* fix(router): match cooldown-duration precedence in the fallback path to the primary path

_trigger_cooldown_for_failed_deployment only checked deployment config before
falling back to the router default, skipping the response Retry-After header
step that Router.deployment_callback_on_failure applies on the primary path.

* fix(router): restore litellm_params.cooldown_time as a pre-existing fallback

cooldown_time already had litellm_params support on Router.deployment_callback_on_failure
before this PR; the earlier model_info-only restriction (aimed at the leak concern
for the genuinely new allowed_fails/allowed_fails_policy fields) incorrectly dropped
that pre-existing capability too. model_info still takes priority when both are set.

* fix(router): keep the fallback-cooldown trigger in sync with #35104's review fixes

Applies the same two fixes landed on the split-out PR #35104 (which #34416
still duplicates until it's rebased onto the merged base): increment the
deployment's per-minute failure counter before evaluating cooldown, and
require the server-stamped failed_deployment_id instead of trusting a
metadata bucket, since neither "metadata" nor "litellm_metadata" can be told
apart from a caller-supplied one without knowing the call's function_name.

* fix(router): freeze the model_info fallback mapping to satisfy the type-discipline gate

* fix(router): defer f-string interpolation in fallback-cooldown debug logs

* fix(router): annotate cooldown-path locals with Final to satisfy the LIT010 budget

* fix(router): suppress reportPrivateUsage for cross-module cooldown helpers

* fix(router): don't cool down deployments for request-scoped 404s on generic API fallbacks

* fix(router): stamp the dynamic client-side-credential deployment id, not the shared static one

* fix(router): keep up with upstream typing modernization and Final-annotation ratchet

* fix(router): don't cool down deployments for a caller-supplied x-litellm-timeout

* fix(router): stamp dynamic client-side-credential id in completion fallback paths too

The generic-API-call helper already stamped the effective (dynamic-if-client-side-credential)
deployment id on exceptions, but the regular _completion/_acompletion exception handlers still
stamped the static shared deployment's id. A tenant using invalid forwarded credentials could
generate repeated failures attributed to, and eventually cooling down, the shared deployment
other tenants rely on. Extracted the stamping logic into one shared helper used by all three
call sites (generic API, sync completion, async completion) so the fix and future changes to it
stay in one place.

* fix(proxy): recognize body-supplied timeout/request_timeout/stream_timeout as caller-controlled

client_side_timeout was only set when the caller used the x-litellm-timeout header, but
Router._get_timeout also resolves the effective timeout from kwargs["timeout"],
kwargs["request_timeout"], and kwargs["stream_timeout"], all settable directly in the
request body (and x-litellm-stream-timeout wasn't marked either). A caller could set any
of those to a near-zero value, force a 408 on every deployment in a fallback chain, and
cool down deployments other tenants rely on without the guard in
_trigger_cooldown_for_failed_deployment recognizing it as caller-controlled. Also strip
any client-forged client_side_timeout from the request body so the marker is always
server-computed.

---------

Co-authored-by: Deepanshu <deepanshu.lulla@alpha-sense.com>
2026-08-10 11:02:06 -07:00
.cargo ci: harden cargo fetches during maturin builds (#31348) 2026-06-25 14:31:05 -07:00
.circleci ci: pin Node on the Playwright UI lanes so npm ci meets the engines floor 2026-08-04 16:31:38 -07:00
.devcontainer build: migrate packaging, CI, and Docker from Poetry to uv (#25007) 2026-04-09 11:46:23 -07:00
.githooks chore(hooks): enforce Conventional Commits and Conventional Branches (#30174) 2026-06-11 10:00:23 -07:00
.github docs: replace the Changes PR template section with Caveats (#36423) 2026-08-10 17:05:47 +00:00
.semgrep/rules security: remove .claude/settings.json and add semgrep rule to prevent re-adding 2026-03-25 11:57:43 -07:00
backend fix(docker): bake the componentized prisma engines at /opt/prisma so any uid can start (#35989) 2026-08-05 13:38:46 -07:00
ci_cd ci: enforce format assertions so calendar-impossible deprecation dates fail validation 2026-07-28 16:11:22 -07:00
cookbook feat(cookbook): add a Grafana dashboard for the OTel GenAI metrics (#35159) 2026-07-30 17:29:40 +00:00
db_scripts fix(db_scripts): pin the tool spend backfill session to UTC 2026-07-27 12:29:19 -07:00
docker fix(docker): fail the image build when the generated prisma engine paths drift off /opt/prisma (#35979) 2026-08-05 14:12:28 -07:00
enterprise fix(proxy): report has_more false on caller-scoped file list pages 2026-08-08 17:28:43 -07:00
examples chore: litellm oss staging (#31185) 2026-06-26 09:17:44 -07:00
gateway fix(docker): bake the componentized prisma engines at /opt/prisma so any uid can start (#35989) 2026-08-05 13:38:46 -07:00
helm docs(helm): replace the classic chart's 128Mi resource example with the documented 4Gi sizing (#35830) 2026-08-04 15:17:12 -07:00
litellm feat(router): add per-deployment allowed_fails_policy and cooldown_time override support (#34416) 2026-08-10 11:02:06 -07:00
litellm-proxy-extras feat(ptu): configure provisioned-throughput flat cost on a model deployment (#35341) 2026-08-10 09:51:16 -07:00
litellm-rust refactor(rust): make litellm-core the callable messages() SDK; drop the ai-gateway handler (#35044) 2026-07-29 13:41:31 -07:00
migrations fix(docker): bake prisma offline in the componentized migrations image (#35485) 2026-08-01 14:12:31 -07:00
packaging/homebrew feat(cli): per-agent lite claude / codex / opencode commands that wrap coding agents through the proxy (#29850) 2026-06-10 13:52:26 -07:00
scripts Merge pull request #36277 from BerriAI/litellm_make_check_fallback 2026-08-08 12:08:34 -07:00
terraform feat(terraform): sync provider 0.3.0 from mirror and cut 0.4.0 2026-08-06 09:49:13 -07:00
tests feat(router): add per-deployment allowed_fails_policy and cooldown_time override support (#34416) 2026-08-10 11:02:06 -07:00
ui feat(ptu): surface PTU flat cost on the daily activity read path (#35391) 2026-08-10 10:55:55 -07:00
.dockerignore build(docker): build the Admin UI from source in a build-platform-pinned stage (#31130) 2026-06-25 23:41:08 -07:00
.env.example Add new model provider Novita AI (#7582) (#9527) 2025-05-12 21:49:30 -07:00
.git-blame-ignore-revs chore: ignore the mechanical lint and typing sweeps in git blame 2026-08-06 11:39:34 +00:00
.gitattributes feat(ui): generate dashboard API types from the proxy OpenAPI spec (#29816) 2026-06-05 17:20:01 -07:00
.gitguardian.yaml build: migrate packaging, CI, and Docker from Poetry to uv (#25007) 2026-04-09 11:46:23 -07:00
.gitignore fix(lint): measure the basedpyright budget gate in a gate-owned venv 2026-08-05 21:33:24 -07:00
.npmrc [Fix] CI/Tooling: Correct min-release-age value in .npmrc files 2026-04-29 19:49:27 -07:00
AGENTS.md docs: hand-written CLAUDE.md; point GEMINI.md and AGENTS.md at it (#29252) 2026-05-29 00:05:05 -07:00
ARCHITECTURE.md feat(litellm): add models and repository layers (#29686) 2026-06-06 20:59:33 -07:00
basedpyright-code-budget.json chore(typing): remove 914 basedpyright Any errors across 16 hotspot files 2026-08-10 01:24:40 -07:00
CLAUDE.md docs: clarify the CLAUDE.md comment exceptions are any-of 2026-08-10 16:49:04 +00:00
codecov.yaml feat(jwt): fall back to DB team memberships when JWT has no team claims (#31356) 2026-07-06 17:17:10 -07:00
CONTRIBUTING.md chore(ci): retire daily OSS branches in favor of litellm_internal_staging 2026-07-20 11:38:52 -07:00
cosign.pub [Infra] Add release workflow and cosign public key 2026-03-31 14:30:27 -07:00
docker-compose.hardened.yml [Feature] Download Prisma binaries at build time instead of at runtime for Security Restricted environments (#17695) 2025-12-16 21:25:53 +05:30
docker-compose.yml feat: add read-replica routing for Prisma DB via DATABASE_URL_READ_REPLICA (#27493) 2026-05-08 21:05:50 -07:00
Dockerfile fix(docker): fail the image build when the generated prisma engine paths drift off /opt/prisma (#35979) 2026-08-05 14:12:28 -07:00
GEMINI.md docs: hand-written CLAUDE.md; point GEMINI.md and AGENTS.md at it (#29252) 2026-05-29 00:05:05 -07:00
LICENSE refactor: creating enterprise folder 2024-02-15 12:54:13 -08:00
license_cache.json Add granian as a ASGI compliant web server. Provider better throughput stability, (#26027) 2026-05-21 19:08:37 -07:00
Makefile build(lint): rename make pre-commit to make check with a working-tree fallback 2026-08-08 03:25:35 -07:00
mcp_servers.json Add ScrapeGraph MCP server configuration (#18923) 2026-01-11 21:57:46 +05:30
model_prices_and_context_window.json fix(bedrock): enable native structured output for GLM 5 and DeepSeek V3.2 (#35669) 2026-08-10 10:18:13 -07:00
model_prices_and_context_window.schema.json fix(pricing): regenerate model prices schema for flex long-context fields 2026-07-30 21:23:59 -07:00
osv-scanner.toml build(deps): defer the second pypdf advisory until the 6.15.0 bump 2026-08-07 19:58:22 +00:00
package-lock.json chore(deps): refresh dependency locks 2026-05-04 11:36:18 -07:00
package.json chore(deps): refresh dependency locks 2026-05-04 11:36:18 -07:00
policy_templates.json feat: Add Canadian PII protection (PIPEDA) (#22951) 2026-03-06 18:27:31 -08:00
prometheus.yml build(docker-compose.yml): add prometheus scraper to docker compose 2024-07-24 10:09:23 -07:00
provider_endpoints_support.json feat: add Meta Model API provider and muse-spark-1.1 (day-0) (#32701) 2026-07-09 20:45:27 -07:00
proxy_server_config.yaml fix(ci): let the E2E proxy accept the mock testing params its suite sends 2026-08-01 14:57:42 -07:00
pyproject.toml bump: litellm-enterprise 0.1.53 -> 0.1.54, litellm-proxy-extras 0.4.83 -> 0.4.84 2026-08-06 17:01:15 -07:00
pyrightconfig.json test(e2e): move Admin UI Playwright suite to tests/e2e/ui (#34196) 2026-07-22 19:43:10 +00:00
qa_sticky_session.sh feat(sandbox): reuse e2b container across requests when metadata.session_id is set (#31688) 2026-06-30 18:58:09 -07:00
README.md chore: keep it concise 2026-07-11 20:32:34 -07:00
render.yaml build(render.yaml): fix health check route 2024-05-24 09:45:28 -07:00
router_plugins.json feat(router): add router plugin reference catalog (#33746) 2026-07-17 18:46:20 +00:00
ruff-strict-budget.json chore(typing): remove 914 basedpyright Any errors across 16 hotspot files 2026-08-10 01:24:40 -07:00
ruff-strict.toml feat(logging): add opt-in session_id and trace_id correlation to JSON log records via contextvars (#34418) 2026-08-10 10:40:13 -07:00
ruff.toml refactor(lint): graduate the 35 zero-violation strict rules into ruff.toml 2026-08-07 23:10:33 -07:00
schema.prisma feat(ptu): configure provisioned-throughput flat cost on a model deployment (#35341) 2026-08-10 09:51:16 -07:00
security.md docs(security): require a reproduction video for vulnerability reports (#30048) (#30063) 2026-06-09 14:59:50 -07:00
taplo.toml fix(agentcore): simplify agentcore streaming (#17141) 2026-01-19 05:20:24 -08:00
type-discipline-budget.json chore(typing): remove 914 basedpyright Any errors across 16 hotspot files 2026-08-10 01:24:40 -07:00
uv.lock build(deps): bump gitpython to 3.1.58, defer pypdf advisory 2026-08-07 19:23:57 +00:00

🚅 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 Deploy on AWS Deploy on GCP

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

PyPI Version GitHub Stars Y Combinator W23 Whatsapp Discord Slack CodSpeed

LiteLLM AI Gateway

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 — set protocolVersion to 1.0 or 0.3 per agent

Step 2. Call Agent via A2A SDK (requires a2a-sdk>=1.1.0)

import httpx
from a2a.client import A2ACardResolver, ClientConfig, ClientFactory
from a2a.types import Message, Part, Role, SendMessageRequest
from a2a.utils.constants import TransportProtocol
from uuid import uuid4

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, timeout=60.0) as http_client:
    resolver = A2ACardResolver(httpx_client=http_client, base_url=base_url)
    agent_card = await resolver.get_agent_card()
    config = ClientConfig(
        httpx_client=http_client,
        streaming=False,
        supported_protocol_bindings=[TransportProtocol.JSONRPC, TransportProtocol.HTTP_JSON],
    )
    client = ClientFactory(config).create(agent_card)

    request = SendMessageRequest(
        message=Message(
            message_id=uuid4().hex,
            role=Role.ROLE_USER,
            parts=[Part(text="Hello!")],
        )
    )
    async for event in client.send_message(request):
        populated = event.ListFields()
        if populated and populated[0][0].name in ("message", "msg"):
            print("".join(getattr(p, "text", "") or "" for p in populated[0][1].parts))

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)
ModelScope (modelscope)
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)
Pinstripes (pinstripes)
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.

Deploy on AWS or GCP with Terraform

Run the LiteLLM proxy as a production-ready componentized stack (gateway, backend, UI on separate services; managed Postgres + Redis + object store) using the published Terraform modules. Both modules are on the public Terraform Registry — no auth needed.

AWS — ECS Fargate + Aurora + ElastiCache + ALB

Launch in AWS CloudShell — opens an in-browser shell, already authenticated to your AWS account. Once inside, run:

git clone https://github.com/BerriAI/litellm.git
cd litellm/terraform/litellm/aws/examples/default
cp terraform.tfvars.example terraform.tfvars   # edit region/tenant/env
terraform init && terraform apply

Module page →

Or call the module from your own root config:

# main.tf
terraform {
  required_version = ">= 1.6.0"
  required_providers {
    aws = { source = "hashicorp/aws", version = "~> 5.60" }
  }
}

provider "aws" {
  region = "us-west-2"
}

module "litellm" {
  source  = "BerriAI/litellm/aws"
  version = "~> 1.89"

  region = "us-west-2"
  azs    = ["us-west-2a", "us-west-2b"]
  tenant = "acme"
  env    = "prod"

  # Production: provide an ACM cert. Without one, set allow_plaintext_alb = true
  # (dev/trial only).
  # acm_certificate_arn = "arn:aws:acm:us-west-2:111122223333:certificate/..."
  allow_plaintext_alb = true
}

output "litellm_url" {
  value = module.litellm.alb_dns_name
}
terraform init
terraform apply

Provider API keys live in AWS Secrets Manager; reference ARNs via gateway_extra_secrets. Full input list and architecture diagram on the registry page.

GCP — Cloud Run + Cloud SQL + Memorystore + HTTPS LB

Open in Cloud Shell

Real 1-click. Opens Cloud Shell, clones this repo, and walks you through terraform apply via a built-in DeployStack tutorial — pick the project, the tutorial sets up the Artifact Registry remote repo, writes terraform.tfvars from your answers, and runs apply.

Module page →

To call the module from your own config instead, Cloud Run can't pull from ghcr.io directly, so first set up a one-time Artifact Registry remote repo backed by GHCR:

gcloud artifacts repositories create litellm \
  --location=us-central1 \
  --repository-format=docker \
  --mode=remote-repository \
  --remote-docker-repo=https://ghcr.io \
  --project=my-gcp-project

Then:

# main.tf
terraform {
  required_version = ">= 1.6.0"
  required_providers {
    google      = { source = "hashicorp/google",      version = "~> 6.10" }
    google-beta = { source = "hashicorp/google-beta", version = "~> 6.10" }
  }
}

provider "google"      { project = "my-gcp-project"; region = "us-central1" }
provider "google-beta" { project = "my-gcp-project"; region = "us-central1" }

module "litellm" {
  source  = "BerriAI/litellm/google"
  version = "~> 1.89"

  project_id = "my-gcp-project"
  region     = "us-central1"
  tenant     = "acme"
  env        = "prod"

  # Replace my-gcp-project with your GCP project ID (same value as project_id above).
  image_registry = "us-central1-docker.pkg.dev/my-gcp-project/litellm/berriai"

  # Production: provide DNS already pointing at the LB IP for Google-managed certs.
  # Without one, set allow_plaintext_lb = true (dev/trial only).
  # lb_domains         = ["proxy.example.com"]
  allow_plaintext_lb = true
}

output "litellm_url" {
  value = module.litellm.load_balancer_url
}
terraform init
terraform apply

Provider API keys live in Secret Manager; reference resource IDs (e.g. projects/my-gcp-project/secrets/openai-api-key) via gateway_extra_secrets. Full input list and architecture diagram on the registry page.

Both stacks include

  • The full componentized split (gateway / backend / UI as independent services)
  • Managed Postgres (writer + reader) and Redis
  • Versioned object store for proxy state + file uploads
  • An auto-generated LITELLM_MASTER_KEY in your cloud's secret manager
  • A one-off migration job that runs prisma migrate deploy before the proxy starts
  • The same proxy_config surface as the Helm chart — pass YAML as a typed map

The Terraform modules live at terraform/litellm/aws/ and terraform/litellm/gcp/ in this repo; the registry entries are read-only mirrors updated on each release.

Run in Developer Mode

Services

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

Backend

  1. Run make bootstrap
  2. Start proxy backend: uv run python litellm/proxy/proxy_cli.py

Frontend

  1. Navigate to ui/litellm-dashboard (dependencies were already installed w/ make bootstrap)
  2. Start dashboard: npm run dev

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