LangSmith
AI Agent & LLM Observability Platform
VS
PromptLayer
Version, test, and monitor every prompt and agent.
Detailed comparison
Criteria
LangSmith
PromptLayer
Pricing
Freemium
Freemium
Plans & pricing
Developer: Free, Team: $39/mo, Enterprise: Custom
Free for hackers: Free, Dataset Pay-as-you-go: Custom, Enterprise: Custom
Free trial
No
Yes
Audience
b2b
b2b
Platforms
Web
Web
API
Yes
Yes
Open Source
Proprietary
Proprietary
Integrations
Pagerduty
—
Categories
Data Science, Dev Tools
Data Science, Dev Tools
Popularity
Very High
Very High
Description
LangSmith is a comprehensive AI agent and LLM observability platform. It provides tracing and real-time monitoring to help developers debug agents, id...
PromptLayer allows you to version, test, and monitor your prompts and AI agents. It offers robust evaluations, tracing, and regression sets to ensure ...
Pricing
LangSmith
Freemium
PromptLayer
Freemium
Plans & pricing
LangSmith
Developer: Free, Team: $39/mo, Enterprise: Custom
PromptLayer
Free for hackers: Free, Dataset Pay-as-you-go: Custom, Enterprise: Custom
Free trial
LangSmith
No
PromptLayer
Yes
Audience
LangSmith
b2b
PromptLayer
b2b
Platforms
LangSmith
Web
PromptLayer
Web
API
LangSmith
Yes
PromptLayer
Yes
Open Source
LangSmith
Proprietary
PromptLayer
Proprietary
Integrations
LangSmith
Pagerduty
PromptLayer
—
Categories
LangSmith
Data Science, Dev Tools
PromptLayer
Data Science, Dev Tools
Popularity
LangSmith
Very High
PromptLayer
Very High
Description
LangSmith
LangSmith is a comprehensive AI agent and LLM observability platform. It provides tracing and real-time monitoring to help developers debug agents, id...
PromptLayer
PromptLayer allows you to version, test, and monitor your prompts and AI agents. It offers robust evaluations, tracing, and regression sets to ensure ...
Features
LangSmith
SDKs for Python, TypeScript, Go, and Java
Message threading for multi-turn chat interactions
Cost tracking
Online LLM-as-judge and code evals
Tool and agent trajectory monitoring
Webhook and Pagerduty alerts
PromptLayer
Prompt Versioning
Agent Testing
Prompt Monitoring
Robust Evaluations
Visual Editor
Key differentiators
LangSmith
- Complete AI agent & LLM observability
- Real-time tracing, debugging & evals
- Cost, latency & trajectory monitoring
PromptLayer
- Full LLM observability & lifecycle management
- Prompt versioning, A/B testing, caching
- Human & automated LLM evaluation
Other comparisons
FAQ: LangSmith vs PromptLayer
LangSmith: AI Agent & LLM Observability Platform. PromptLayer: Version, test, and monitor every prompt and agent.. Both tools take different approaches to address similar needs.
Both offer a free or freemium plan. LangSmith is freemium and PromptLayer is freemium.
The best choice between LangSmith and PromptLayer depends on your specific needs. Compare their features, pricing, and target audience on this page to find the tool that best fits your use case.
Both are primarily designed for individuals. The choice depends on which specific features you need.
LangSmith offers: SDKs for Python, TypeScript, Go, and Java, Message threading for multi-turn chat interactions, Cost tracking, Online LLM-as-judge and code evals. PromptLayer offers: Prompt Versioning, Agent Testing, Prompt Monitoring, Robust Evaluations.
Based on our data, LangSmith currently enjoys greater popularity. However, popularity isn't the only factor — compare features to find the right tool for your needs.