Ship AI Apps With
Fewer Surprises

Debug prompts, run tests, and observe what’s happening in production.
Speed up your AI development workflow with Langtail.

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GoodlokDeepnoteMangowebWopeMockuuups Studio


Debug prompts

Iterate at Lightning Speed
Fine-tune prompts and settings to optimize your LLM's performance in record time.
Use advanced features
Support for variables, tools (functions), vision and more built right in.
Instant Feedback Loop
See how prompt changes affect your AI's output instantly.
Version History
Roll back to previous prompt versions with full version history.
Langtail Playground


Run tests

Prevent surprises
Make changes your prompts and rely on your test suite to make sure you aren’t breaking your app instead of manual testing.
Benchmark prompt variations
Run tests on different prompt versions to identify the top-performing one.
Upgrade models with confidence
Ensure your app's stability when moving to new model versions by leveraging your test suite.
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Deploy prompts

Iterate faster
Publish your prompts as API endpoints, allowing you to make changes without redeploying your entire application.
Fit your development workflow
Deploy prompts to separate preview, staging, and production environments to keep everything aligned with the way your team ships.
Decouple prompts from code
Separate prompt development from app development, enabling your team to work more independently and efficiently.
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Monitor Production

Detailed API Logging
Capture performance data, token count, and LLM costs for every API call to the LLM.
Metrics Dashboard
View aggregated prompt performance metrics including request count, cost, and latency.
Problem Detection
Identify issues by monitoring user interactions with your app in production.
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Engineering and AI teams Langtail

“Langtail simplifies the development and testing of Deepnote AI, enabling our team to focus on further integrating AI features into our product”

Ondřej Romancov
Software Engineer at Deepnote

“If you're continuously optimizing your LLMs and not using a logging solution, you're seriously missing out. As a prompt engineer, I absolutely love the freedom to test whatever I want independently of the backend team. And finally, we see this within a quality user interface.”

Yiğit Konur
Head of AI at Wope

Ready to upgrade your AI dev workflow?

Langtail is the most enjoyable way to debug, test, and observe LLM-powered apps. Try it for free, no credit card needed.