OpenLIT review

Q: How do I install OpenLIT?

Run pip install openlit. It needs Node.js >=18.0.0. The install section above has the other options from the project's README.

OpenLIT is an open-source, self-hosted platform for tracing, evaluating, guarding, and improving AI agents and coding agents on OpenTelemetry.

Updated Nov 1, 2026. Review written Oct 22, 2026 from the project's own sources; usage data refreshed every Monday.

TL;DR

OpenLIT is an open-source agent harness engineering platform with OpenTelemetry-native tracing, evals, guardrails, prompt management, and cost and GPU monitoring. It is for teams running AI agents or coding agents in production. OpenLIT is free to self-host under Apache 2.0, follows OpenTelemetry GenAI semantic conventions, and can export to other OTLP backends.

2.9kGitHub stars
+16new stars, week of Oct 25
~88.1kdownloads a week, +11% vs 4-week avg
#12in Evals and observability this week

OpenLIT at a glance

Category: Evals and observability
Maintained by: OpenLIT (organization, @openlit on GitHub)
License: Apache 2.0
Language: TypeScript, Python, Go
Repository: github.com/openlit/openlit
Website: docs.openlit.io
npm package: openlit 1.15.0
PyPI package: openlit 1.45.0
Latest release: otel-gpu-collector-1.0.0 on GitHub, Oct 13, 2026
First published: Jan 23, 2024

What OpenLIT does

OpenLIT traces LLM calls, tool calls, MCP requests, retrieval, and agent steps as OpenTelemetry traces and metrics.
OpenLIT runs evaluations on real traces using LLM-as-a-judge, programmatic checks, human feedback, and CI gates.
OpenLIT SDK guardrails detect and block prompt injection, jailbreak attempts, sensitive topics, and off-topic requests at runtime.
OpenLIT captures coding-agent sessions from Claude Code, Cursor, Codex, and OpenCode, including tool calls, token usage, cost, and code impact.
OpenLIT tracks LLM cost with custom pricing and monitors NVIDIA, AMD, and Intel GPUs used for inference.
OpenLIT Prompt Hub stores versioned prompts, and Vault stores API keys retrieved at runtime via SDK or API.
OpenLIT OpenGround runs the same prompt across multiple providers to compare cost, latency, and output quality.

How it works

OpenLIT runs in your infrastructure with Docker or Kubernetes. Your app sends telemetry over OTLP to the OpenLIT receiver on ports 4317 (gRPC) or 4318 (HTTP). Data is stored in ClickHouse and shown in the OpenLIT dashboard. Python, TypeScript, and Go SDKs auto-instrument supported providers and frameworks. You can place your own OpenTelemetry Collector in front to fan out to other backends.

How to install and start using OpenLIT

Python SDK with pip

pip install openlit

TypeScript SDK with npm

npm install openlit

Requirements

Python 3.9 or later (below 4.0) for the Python SDK.
Node.js 18.0.0 or later for the TypeScript SDK.
Docker or Kubernetes to self-host the OpenLIT platform.

First steps

Start OpenLIT with Docker Compose and open http://127.0.0.1:3000 in a browser.
Install the Python or TypeScript SDK and call openlit.init() in your application.
Point telemetry at the OTLP endpoint by setting OTEL_EXPORTER_OTLP_ENDPOINT to http://127.0.0.1:4318.
For coding agents, install the CLI, then run openlit coding install --vendor=all and check with openlit doctor.

Who OpenLIT is for

Teams running AI agents in production who want traces, evals, and guardrails in one self-hosted tool.
Developers who want to see what Claude Code, Cursor, Codex, or OpenCode did during a session.
Teams with an existing OpenTelemetry setup who want GenAI telemetry without a proprietary format.
Teams serving LLMs on their own NVIDIA, AMD, or Intel GPUs.

Limitations to know

OpenLIT is not an agent framework or harness runtime and does not run your agent loop.
OpenLIT self-hosting means you operate the deployment, including its ClickHouse storage.
OpenLIT's TypeScript SDK package on npm lists an ISC license, while the repository and Python package list Apache-2.0.

Is OpenLIT growing? Usage data

In the week of Oct 25–31, 2026, OpenLIT ranked #249 on the Devtoolwatch Board and #12 in Evals and observability, with a momentum score of 38 out of 100. Its main package had about 88.1k downloads that week, +11% against its own 4-week average.

New GitHub stars per week for the last 12 weeks, from GitHub's stargazer history (today's stargazers by the week they starred).

Show the weekly numbers

New GitHub stars per week for OpenLIT
Week of	New stars
Aug 9, 2026	16
Aug 16, 2026	22
Aug 23, 2026	15
Aug 30, 2026	16
Sep 6, 2026	18
Sep 13, 2026	13
Sep 20, 2026	26
Sep 27, 2026	19
Oct 4, 2026	26
Oct 11, 2026	20
Oct 18, 2026	28
Oct 25, 2026	16

On Hacker News

Show HN: OpenLIT – Open-Source LLM Observability with OpenTelemetry, 62 points and 22 comments (Apr 26, 2024)

The Board ranks tools by four signals each week: new stars, new stars for the repo's size, added downloads and download growth beyond the market. How the ranking works.

OpenLIT alternatives

Other LLM evals and observability tools on the Board in the week of Oct 25–31, 2026, by momentum:

Evals and observability ranked by momentum, the week of Oct 25–31, 2026
Rank	Tool	Stars	Downloads/wk
#1	SkillSpectorSkillSpector is NVIDIA's security scanner that checks AI agent skills for vulnerabilities, malicious patterns, and supply-chain risks…	23.7k	–
#2	JudgevalJudgeval is an open-source Python SDK for tracing and evaluating LLM-powered agents with prompt-based judges and online monitoring.	1.1k	80.2k
#3	A.I.G (AI-Infra-Guard)A full-stack AI Red Teaming platform securing AI ecosystems via Agent Scan, Skills Scan, MCP scan, AI Infra scan and LLM jailbreak…	7.2k	–
#4	LangfuseLangfuse is an open source LLM engineering platform for tracing, evaluating, prompt management, and debugging LLM applications and agents.	36.8k	9.8M
#5	OpikOpik is an open-source platform from Comet for tracing, evaluating, and monitoring LLM applications, RAG systems, and AI agents.	23.1k	709.1k
#6	promptfoopromptfoo is a CLI and library for evaluating and red-teaming LLM-based apps, including prompts, agents, and RAG pipelines.	26.7k	1.2M

All LLM evals and observability tools, ranked

Recent OpenLIT releases

otel-gpu-collector-1.0.0, Oct 13, 2026
openlit-2.1.0, Sep 10, 2026
openlit-2.0.0, Aug 28, 2026
otel-gpu-collector-0.0.8, Aug 26, 2026
ts-1.15.0, Aug 3, 2026

OpenLIT FAQ

Is OpenLIT free and open source?

Yes. OpenLIT's source code is on GitHub (openlit/openlit) under the Apache 2.0 license, so you can use it for free.

How do I install OpenLIT?

Run pip install openlit. It needs Node.js >=18.0.0. The install section above has the other options from the project's README.

Is OpenLIT still maintained?

Yes. The openlit/openlit repository was last updated on Oct 21, 2026, and the latest release, otel-gpu-collector-1.0.0 on GitHub, came out on Oct 13, 2026.

How popular is OpenLIT?

OpenLIT has 2.9k GitHub stars as of Nov 1, 2026. It gained 16 new stars in the week of Oct 25–31, 2026, against a 12-week average of 20 a week. Its main package had about 88.1k downloads that week, +11% against its own 4-week average. That made it #12 among LLM evals and observability tools on the Devtoolwatch Board.

OpenLIT vs Langfuse: how do they compare?

OpenLIT and Langfuse are both tracked by Devtoolwatch as LLM evals and observability tools. OpenLIT has 2.9k GitHub stars and Langfuse has 36.8k. In the week of Oct 25–31, 2026, OpenLIT's main package had 88.1k downloads and Langfuse's had 9.8M. Langfuse is an open source LLM engineering platform for tracing, evaluating, prompt management, and debugging LLM applications and agents. Langfuse review.

OpenLIT vs OpenLLMetry: how do they compare?

OpenLIT and OpenLLMetry are both tracked by Devtoolwatch as LLM evals and observability tools. OpenLIT has 2.9k GitHub stars and OpenLLMetry has 7.5k. OpenLLMetry is an open-source set of OpenTelemetry extensions that adds observability to LLM applications, with instrumentations for LLM providers, vector DBs and frameworks. OpenLLMetry review.

What are the best alternatives to OpenLIT?

Other LLM evals and observability tools on the Devtoolwatch Board in the week of Oct 25–31, 2026, by momentum: SkillSpector (#1), Judgeval (#2), A.I.G (AI-Infra-Guard) (#3), Langfuse (#4), Opik (#5). The alternatives table above has their numbers.

Is OpenLIT built on OpenTelemetry?

Yes. OpenLIT is OpenTelemetry-native. Traces and metrics follow the OpenTelemetry GenAI semantic conventions (gen_ai.*), and telemetry can flow through your own Collector to other OTel backends such as Datadog, Grafana, or Honeycomb.

Does OpenLIT replace my agent framework?

No. OpenLIT does not run your agent loop. OpenLIT instruments the harness you already use, such as LangGraph, CrewAI, or the OpenAI Agents SDK, through OpenTelemetry.

Does OpenLIT work with Claude Code, Codex, and Cursor?

Yes. The openlit CLI ingests each coding agent's hook events and maps them to OpenTelemetry gen_ai.* conventions, with no SDK and no code changes.

Do I need an OpenTelemetry Collector to use OpenLIT?

No. OpenLIT listens for OTLP directly on port 4317 (gRPC) and 4318 (HTTP). You can still put your own Collector in front for fan-out or processing.

What does an OpenLIT guardrail detect?

OpenLIT SDK guardrails detect prompt injection and jailbreak attempts, sensitive topics, and topic restriction violations. Guardrail checks are traced with OpenTelemetry, so you can see when and why a request was blocked.

Sources

OpenLIT README badge

Maintainers can show the tool's weekly Board rank in their README:

[![Devtoolwatch](https://index.devtoolwatch.com/badge/openlit.svg)](https://index.devtoolwatch.com/tools/openlit/)

How this page is made: Devtoolwatch writes each review from the project's README, releases, package metadata and website, with an AI model, then checks every claim against the source it cites and drops what the sources don't support. The numbers come from Devtoolwatch's daily GitHub snapshots, GitHub's stargazer history, and the npm and PyPI download APIs. Spotted an error? Email [email protected].