Prompt Optimizer vs PromptLayer

Prompt Optimizer has no write-up on Specifiction yet; its figures are above.

PromptLayer combines a prompt registry and visual prompt CMS with evaluations, observability, and agent tracing for teams building AI products. Teams can visually edit, version, test, and deploy prompts without waiting for an application redeploy, allowing domain experts and non-technical stakeholders to work alongside engineers. Evaluations can run when prompt versions change, through the API, or on demand in the UI. They include historical backtests and side-by-side model comparisons. Tracking covers requests, traces, cost, latency, token usage, scores, and custom metadata, with OpenTelemetry span support. The OpenAI integration includes versioned prompts, release labels, request observability, evaluations, and model comparisons. Free, Pro, and Team are cloud-hosted in the US; Enterprise offers self-hosting on GCP, AWS, or Azure, EU cloud hosting, or single-tenant cloud hosting. PromptLayer states that it maintains SOC 2 Type 2, HIPAA, GDPR, and CCPA compliance. Free costs nothing, Pro costs $49 a month, and Team costs $500 a month. Enterprise pricing is custom.