Helicone vs TensorZero

Helicone routes, debugs, and analyzes AI applications through a gateway and observability tools. The gateway provides access to more than 100 models through the OpenAI SDK by changing the model name, and supports load balancing, automatic failovers, and response caching across providers. Helicone logs requests in real time and visualizes multi-step LLM interactions to help locate error causes. Listed integrations include OpenAI, Anthropic, Azure, LiteLLM, Anyscale, Together AI, and OpenRouter. It can run in customer infrastructure through single-click deployment or a production-ready Helm chart; Helicone also states that its cloud is SOC 2, HIPAA, and GDPR compliant. A LangGraph integration tracks calls, sessions, performance, and costs, while an API cost calculator covers more than 300 models and providers. The free Hobby plan includes 10,000 requests, 1 GB storage, one seat, one organization, and seven days of retention. Pro costs $79.00 per month. A seven-day trial is advertised. Helicone says its services remain live in maintenance mode following acquisition by Mintlify, with security updates, new models, and bug and performance fixes continuing.

TensorZero is a free, open-source stack that brings together an LLM gateway, observability, optimization, evaluation, and experimentation. Its gateway provides a unified API for model providers and supports routing, retries, fallbacks, prompt templates, schemas, multi-step workflows, and traffic routing for A/B tests. Documented integrations include Anthropic, AWS Bedrock, Azure, Google, OpenAI, OpenRouter, Together AI, vLLM, xAI, and OpenAI-compatible endpoints. Inference and feedback data go to the database you configure, where they can be queried with SQL; feedback can be tied to individual inferences or episodes. The gateway and UI can run through Docker, Docker Compose, Kubernetes and Helm, or a source build. API key authentication is available for gateway endpoints other than status and health checks. The project is available on GitHub, but is no longer maintained; its repository is archived and read-only. TensorZero is self-hosted and licensed under Apache 2.0. It collects pseudonymous aggregate usage analytics, excluding application data and inference inputs and outputs, with an option to disable collection.