Google Cloud Agent Evaluation vs Opik

Google Cloud Agent Evaluation helps measure and improve agent performance, safety, and quality. Its workflow runs from defining evaluation cases through inference, behavior-trace capture, metric calculation, result analysis, and optimization. It can generate varied, multi-turn test scenarios from agent instructions and tool definitions, and intercept tool calls to supply custom behavior, mocked data, or simulated errors such as HTTP 503 responses and latency spikes. Prebuilt or custom raters score traces with reference-based Exact Match or reference-free Helpfulness metrics. Teams can also evaluate production-traffic traces or external logs without a managed test environment. Prompt optimization identifies failure points and proposes focused system-instruction changes. The service supports tool-call checks, safety evaluations, regression runs, trace ingestion, and custom models. Access is through API or web, with notebook launch options for Colab, Colab Enterprise, Agent Platform Workbench, and GitHub. Pricing is usage-based: $0.00003 per 1k input characters and $0.00009 per 1k output characters for computation-based metrics; model-based metrics also incur underlying autorater model costs. New Google Cloud customers get $300 in trial credits.

Opik helps teams building applications or agents that call an LLM log actions and evaluate behavior across development, testing, and production. It captures and visualizes traces, supports annotation, and provides audit logs. Its evaluation tools include more than 30 metrics for outcomes such as answer relevance, context precision, task completion, and hallucination. In production, Opik can evaluate traces in real time, alert when criteria fail, and track token use and model costs. Test Suites offer pass/fail assertions, an Agent Playground supports end-to-end tests, and a Prompt Optimizer provides six algorithms. Core observability and evaluation features are available as open-source code for local use. Opik includes a REST API and Python client, with Python and TypeScript SDKs listed, and integrations with more than 40 frameworks, model providers, and gateways. Free Cloud allows up to 10 team members, 25,000 spans per month, and 60-day retention. Pro Cloud costs $19 a month and lists up to 50 team members and 100,000 spans monthly.