PromptLayer
Free tierThe collaboration layer for AI engineering teams — prompt CMS, eval harness, and observability stack
Key strengths
Facts verified against promptlayer.com on
Get alerts when PromptLayer changes
Free. We'll email you when pricing, the free tier, API access or open-source status changes.
PromptLayer is an open-source, self-hostable collaboration and observability platform built for AI engineering teams shipping LLM-powered applications. It exposes a REST API and SDK for integrating prompt versioning, a centralized prompt registry, and a visual CMS directly into CI/CD pipelines. Engineers instrument their LLM calls to capture full production traces, linking each request back to the exact prompt version that generated it. The evaluation harness supports dataset-backed regression tests, human review workflows, and LLM-as-a-judge graders, enabling systematic quality gates before deployment. Cost, latency, and token usage metrics are tracked per request. PromptLayer is SOC 2 Type 2, HIPAA, and GDPR compliant. It was founded in 2022, is headquartered in New York City, and has 784 GitHub stars. Pricing starts at $0 (free tier, 5 users, 2,500 requests/month), with a Pro plan at $49/month, Team at $500/month (25 users, 100k+ requests/month), and Enterprise at custom pricing. Pay-as-you-go overages are billed at $0.003/txn (Pro) and $0.002/txn (Team).