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
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
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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 (2 days ago)
- Last release
- Oct 21, 2026 (5 days ago)
From GitHub (fetched Oct 24, 2026).
Details
- License
- Apache-2.0
- Repository
- github.com/langwatch/langwatch
- Website
- langwatch.ai
- First seen
- Oct 24, 2026
- Last checked
- Oct 24, 2026
Cite this page
LangWatch. Agent Mart. https://agentmart.dev/observability/langwatch (last updated 2026-10-24)