devtools

Test AI with Langwatch

Evaluate LLMs and AI agents with Langwatch, a platform for founders working with AI technologies
3,525 stars365 forksTypeScriptGuide quality 9/10Updated 9/8/2026100% free · open source
What it does

Langwatch evaluates and tests Large Language Models (LLMs) and AI agents to help founders assess their performance and capabilities.

When to use it
  • When selecting an LLM for a specific task or project
  • When comparing the performance of different LLMs or AI agents
  • When testing and fine-tuning LLMs or AI agents for a particular use case
Ready-to-paste prompt
langwatch --llm gpt-3 --task text-classification --dataset my-dataset.json
Heads up: Langwatch requires a GitHub personal access token to fetch LLM models, which must be stored in a .env file at the root of the project
Saves to your device
Use with Claude
New

Skip the builder — one click puts this in Claude, Cursor, Antigravity and more.

🔑 Needs an API key

Works after you add credentials — the setup agent will ask you for them.

Try it instantly — no install
Claude Code
mkdir -p ~/.claude/skills/langwatch && curl -fsSL https://workflowstacks.com/api/skills/langwatch/claude-skill -o ~/.claude/skills/langwatch/SKILL.md
Open in another AI app

Opens the app with this repo with the prompt ready to go — no copy-paste needed.

Connect the whole catalog (MCP)
claude mcp add --transport http workflowstacks https://workflowstacks.com/api/mcp

Adds a WorkflowStacks connector to Claude Code: search and load any skill here by chatting.

Quick Actions
Details
Creator
langwatch
Language
TypeScript
Category
devtools
Published
9/9/2023

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