Enterprise AI Buying Guide
Braintrust and Arize are categorized in the market as LLM evaluation and observability tools, used to test model quality before deployment and to trace and score outputs after the fact. Trussed operates as a runtime governance layer, enforcing agent identity, tool-call permissions, and policy controls during live execution. The two categories address different stages of the AI agent lifecycle and are not substitutes for one another.
Evaluation, observability, and runtime governance map to three distinct stages of an agent's life, from pre-launch testing through live execution.
Offline test sets and quality scoring before an agent goes live.
Tracing, logging, and output scoring after actions have occurred.
Interception of tool calls and policy decisions during execution.
Braintrust and Arize are positioned in the market as LLM evaluation and observability platforms. Their core function is measurement: offline test sets and quality scoring before an agent goes live, and tracing, logging, and output scoring after actions have already occurred. Both stages produce valuable signal about model quality, but neither operates while an agent is actively executing a tool call.