Struct AgentBuilder 

pub struct AgentBuilder { /* private fields */ }

Builder for Agent.

Implementations

impl AgentBuilder

pub fn id(self, id: impl Into<String>) -> AgentBuilder

pub fn name(self, name: impl Into<String>) -> AgentBuilder

pub fn description(self, description: impl Into<String>) -> AgentBuilder

pub fn instructions(self, instructions: impl Into<String>) -> AgentBuilder

pub fn model(self, model: impl Into<String>) -> AgentBuilder

pub fn temperature(self, temperature: f32) -> AgentBuilder

pub fn max_tokens(self, max_tokens: u32) -> AgentBuilder

pub fn response_format(self, format: ResponseFormat) -> AgentBuilder

Request a structured-output response format (e.g. a JSON schema).

pub fn tool(self, tool: ToolDefinition) -> AgentBuilder

Add a tool available to the agent.

pub fn tools( self, tools: impl IntoIterator<Item = ToolDefinition>, ) -> AgentBuilder

Add multiple tools.

pub fn tool_source(self, source: Arc<dyn ToolSource>) -> AgentBuilder

Register a dynamic tool source (e.g. an MCP server wrapper), resolved fresh on every run and appended after the agent’s static/context/ per-run tools (dedup by name against those and any earlier-registered source; first registrant wins). Call repeatedly to register more than one source. See ToolSource, resolved internally by every Agent run.

pub fn context_provider( self, provider: Arc<dyn ContextProvider>, ) -> AgentBuilder

Add a single context provider (repeatable; providers run in registration order, agent providers after any thread-level ones).

pub fn context_providers( self, providers: Vec<Arc<dyn ContextProvider>>, ) -> AgentBuilder

Set the context provider list, replacing any previously registered.

pub fn with_compaction( self, strategy: impl CompactionStrategy + 'static, ) -> AgentBuilder

Attach conversation-history compaction, via a CompactionProvider wrapping strategy (with the default ApproxTokenizer; use AgentBuilder::context_provider with CompactionProvider::with_tokenizer for a custom tokenizer).

Registered as one of the agent’s own context providers, which Agent::combined_providers always runs after the session’s — including the auto-attached (or explicitly attached) HistoryProvider, which lives on the session — so compaction sees, and can shrink, the full history-prepended message list for the run. Not calling this leaves the default behavior unchanged: the full history is sent every run.

pub fn middleware(self, mw: Arc<dyn Middleware<AgentContext>>) -> AgentBuilder

Add an agent middleware.

pub fn chat_middleware( self, mw: Arc<dyn Middleware<ChatContext>>, ) -> AgentBuilder

Add a chat middleware, run around the underlying chat-client call on every request (repeatable, like AgentBuilder::middleware). See the chat-client call pipeline for exactly what it can observe and mutate.

pub fn function_middleware( self, mw: Arc<dyn Middleware<FunctionInvocationContext>>, ) -> AgentBuilder

Add a function-invocation middleware, run around every local tool call (repeatable). Plumbed down into the FunctionInvokingChatClient this builder wraps the underlying client with.

pub fn observability_config(self, config: ObservabilityConfig) -> AgentBuilder

Set the ObservabilityConfig for the execute_tool spans this agent’s tool loop emits — content capture and the GenAI semantic-convention version.

The builder wraps the caller’s client in a FunctionInvokingChatClient itself, so this is the only way to reach that wrapper’s own config. Pass the same value given to an ObservableChatClient around the same client, so one trace reports one convention version across its chat and tool spans. Left unset, the tool loop reads the environment, as it always has.

pub fn chat_options(self, options: ChatOptions) -> AgentBuilder

Override the whole chat options object (advanced).

pub fn build(self) -> Agent

Build the agent.