Models

Implement the model contract and normalize usage and stream output.

Read the walkthrough before consulting individual signatures.

Public interfaces

Interface	Purpose
AgentModel	Protocol implemented by every provider or custom model adapter.
ModelEvent	One provider-neutral event emitted by an AgentModel.
ModelEventType	Streaming events emitted by a model adapter.
ModelRequest	Complete provider-neutral input for one model step.
ModelResponse	Final normalized response for one model step.
ModelUsage	Normalized token and cache measurements reported by a provider adapter.
NativeDeferredToolsModel	An AgentModel that says whether its endpoint can load a deferred tool by reference.
ReasoningEffort	Provider-neutral levels for controlling model reasoning effort.
RetryOptions	Model-owned exponential backoff, without jitter.
ServerToolCall	Provider-executed tool invocation exposed for observation only.
ServerToolDefinition	Opaque provider-hosted tool configuration for one model request.
ServerToolInputDelta	One streamed input fragment for a provider-executed tool invocation.
ServerToolResult	Terminal output from a tool executed inside the provider.
TimeoutOptions	How long a provider may stay silent before the request is given up on.
ToolCallDelta	One streamed fragment of a model-requested tool call.
ToolDefinition	Provider-neutral tool metadata supplied with a model request.