The Stack · Observability & evals (managed) API

Comet Opik

Open-source LLM tracing, LLM-as-a-judge evals and experiment management from Comet, with a managed cloud.

API keyFreemium🔵 agent: self serve instant key

Get API key → instant key, usually no card Docs Website

CategoryObservability & evals (managed)

TypeAPI service

Authapi-key

PricingFreemium

Agent signup🔵 self serve instant key

SDKsPython, TypeScript, REST

Pricing: Opik Cloud free tier + Opik Pro ~$19/mo with higher limits; OSS edition is free/self-hosted (docker compose).

🔵 Agents: self serve instant key

Instant self-serve — free signup gives a key immediately (a human unblocks an agent in under 2 minutes).

Sign up for Comet free and get an API key instantly; `pip install opik` then `opik configure` (or set OPIK_API_KEY/OPIK_WORKSPACE). Self-host needs no key.

Comet Opik — Open-source LLM tracing, LLM-as-a-judge evals and experiment management from Comet, with a managed cloud.
Website: https://www.comet.com/site/products/opik/
Docs: https://www.comet.com/docs/opik/
Get a key: https://www.comet.com/signup
Agent signup: self serve instant key — Sign up for Comet free and get an API key instantly; `pip install opik` then `opik configure` (or set OPIK_API_KEY/OPIK_WORKSPACE). Self-host needs no key.
Auth: api-key
Pricing: freemium — Opik Cloud free tier + Opik Pro ~$19/mo with higher limits; OSS edition is free/self-hosted (docker compose).
Full record: https://dreaming.press/api/tools/comet-opik.json

Machine record: /api/tools/comet-opik.json

Quickstart

# pip install opik ; opik configure  (or set OPIK_API_KEY / OPIK_WORKSPACE)
import opik
from opik.integrations.openai import track_openai
from openai import OpenAI

client = track_openai(OpenAI())

@opik.track
def pipeline(q: str):
    return client.chat.completions.create(
        model="gpt-4o-mini",
        messages=[{"role": "user", "content": q}],
    )

python · full docs →

Comet Opik in our coverage

Braintrust vs Arize vs Opik: Choosing an LLM Eval Platform in 2026

2026-06-26

Comet Opik FAQ

What is Comet Opik?

Comet Opik is Open-source LLM tracing, LLM-as-a-judge evals and experiment management from Comet, with a managed cloud. It's in the Observability & evals (managed) category of the dreaming.press tool directory.

Is Comet Opik free?

Comet Opik is freemium — free to start, paid plans for scale. Opik Cloud free tier + Opik Pro ~$19/mo with higher limits; OSS edition is free/self-hosted (docker compose)..

Can an AI agent sign up for Comet Opik automatically?

Almost — signup is instant and self-serve (a free key with no sales call), so a human can unblock an agent in under two minutes. Sign up for Comet free and get an API key instantly; `pip install opik` then `opik configure` (or set OPIK_API_KEY/OPIK_WORKSPACE). Self-host needs no key..

Does Comet Opik have an MCP server?

Comet Opik does not publish an official MCP server as of our last check.

Is Comet Opik open source?

Comet Opik is a hosted API service, not an open-source project.

What languages does Comet Opik support?

Comet Opik offers Python, TypeScript, REST.

Comet Opik

Quickstart

Comet Opik in our coverage

Braintrust vs Arize vs Opik: Choosing an LLM Eval Platform in 2026

Comet Opik FAQ

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