Details:
* The Sampler allows ADK agent optimizers to request evals and receive detailed eval results that can be used to guide agent optimization.
* This interface allows developers to run custom evaluations if needed for their agent. An implementation to interface with the inbuilt LocalEvalService shall be published shortly in a follow-up PR.
* The AgentOptimizer interface describes the general framework for an ADK agent optimizer that uses the Sampler interface to optimize an ADK agent.
* data_types.py contains generic types and base classes to allow intercommunication between the AgentOptimizer, Sampler, and developer code.
Co-authored-by: Keyur Joshi <keyurj@google.com>
PiperOrigin-RevId: 861849691