LangWatch

Open-source platform to trace, test, evaluate and govern every LLM call and AI agent in production

Observability tool by LangWatch

IndexedApache-2.0★ 4,991

Chalk Labs

Need help deploying LangWatch?

Chalk Labs sets up agents like this inside real teams: connected to your tools, tested on your data, with a human in the loop where it matters.

Book a call

Get started

Setup steps are in the repository. Website · Docs · Repository

About

LangWatch traces every LLM call, tool call and user interaction, and runs agent simulations in which a simulated user tests the agent turn by turn. It evaluates experiments and production traffic, manages versioned prompts, and includes an AI gateway with virtual keys and budgets. It can be self-hosted with a single command.

Use cases: monitoring-observability, llm-evaluation

Reviews

Write a review

No reviews yet. Installed it? Reviews come from verified installers only. How reviews work

Fact sheet

Category: Evals · open source
Self-host: Yesraw.githubusercontent.com
Open source: Yesraw.githubusercontent.com
Compliance (vendor says): ISO 27001langwatch.ai
Works with: langchain, langgraph, vercel-ai-sdk, mastra, crewai, google-adk, dspyraw.githubusercontent.com
Protocols: opentelemetry, mcpraw.githubusercontent.com

Plans

Developer	$0	free forever; 50k events/month; 14-day data access; 2 users; community support
Growth	Contact sales	EUR 29 per core seat per month (not converted); 200k events included then EUR 5 per 100k; 30-day retention; unlimited lite-users
Enterprise	Contact sales	custom; hybrid, self-hosted or on-prem; custom SSO and RBAC; audit logs and SLAs; ISO 27001 reports

From the vendor's pricing page, read Oct 24, 2026.

Facts read from the vendor's own pages by claude-haiku-5-5 on Oct 24, 2026; a fact is shown only with the page it came from.

Signals

Stars: 4,991
Forks: 417
Open issues: 153
Last commit: Oct 24, 2026 (6 days ago)
Last release: Oct 21, 2026 (9 days ago)

From GitHub (fetched Oct 24, 2026).

Details

License: Apache-2.0
Repository: github.com/langwatch/langwatch
Website: langwatch.ai
Docs: langwatch.ai/docs/introduction
First seen: Oct 24, 2026
Last checked: Oct 24, 2026
Source: Website Docs Pricing page README github-graphql

Done for you

Rather not set it up yourself?

Chalk Labs scopes, builds and runs agents for your team: the task audit, the eval harness, the integrations and the weekly ops report. Fixed scope, priced before we start.

See how we build AI agents →Read the case studies

Chalk Labs is a two-founder AI and growth studio. We build AI agents, CRMs and MVPs for Web3 and AI companies, and have shipped 50+ product and token launches.

launches shipped: 50+; launches shipped
media placements: 500+; media placements
founders on every account: 2; founders on every account

Press we've placed: Forbes · CoinDesk · Decrypt · Cointelegraph · The Block

Rahil Jain, Co-founder, Chalk Labs. Ex-Goldman Sachs engineer. You talk to the person who builds it.

Get LangWatch running in your business

Tell us what you want to automate. A founder replies within one working day with a plan, not a pitch deck.

Need help deploying LangWatch?

Call Get help

Cite this page

LangWatch. Agent Mart. https://agentmart.dev/observability/langwatch (last updated 2026-10-24)