Struct SubAgentTool 

pub struct SubAgentTool { /* private fields */ }

A tool that delegates work to a child agent loop.

When the parent LLM calls this tool, it spawns a fresh agent_loop() with its own system prompt, tools, and provider. The sub-agent runs to completion and its final text output is returned as the tool result.

Implementations

impl SubAgentTool

pub fn new(name: impl Into<String>, model_config: ModelConfig) -> Self

Create a new sub-agent tool with a name and model config.

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

Set the parent loop’s loop_id for child → parent ancestry tracking.

When set, this value is placed in the child AgentContext.parent_loop_id, which is then emitted in the child’s AgentStart event. This creates a bidirectional link: the parent sees the child’s loop_id via ToolExecutionEnd.child_loop_id, and the child records the parent via AgentStart.parent_loop_id.

pub fn with_provider_override(self, provider: Arc<dyn StreamProvider>) -> Self

Override the provider used by this sub-agent, bypassing ProviderRegistry dispatch. Primarily used in tests to inject a MockProvider.

pub fn with_description(self, desc: impl Into<String>) -> Self

pub fn with_system_prompt(self, prompt: impl Into<String>) -> Self

pub fn with_tools(self, tools: Vec<Arc<dyn AgentTool>>) -> Self

pub fn with_thinking(self, level: ThinkingLevel) -> Self

pub fn with_max_tokens(self, max: u32) -> Self

pub fn with_cache_config(self, config: CacheConfig) -> Self

pub fn with_tool_execution(self, strategy: ToolExecutionStrategy) -> Self

pub fn with_retry_config(self, config: RetryConfig) -> Self

pub fn with_max_turns(self, max: usize) -> Self

Trait Implementations

impl AgentTool for SubAgentTool

fn name(&self) -> &str

Unique tool name (used in LLM tool_use)

fn label(&self) -> &str

Human-readable label for UI

fn description(&self) -> &str

Description for the LLM

fn parameters_schema(&self) -> Value

JSON Schema for parameters

fn execute<'life0, 'async_trait>( &'life0 self, params: Value, ctx: ToolContext, ) -> Pin<Box<dyn Future<Output = Result<ToolResult, ToolError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Execute the tool.

fn timeout(&self) -> Option<Duration>

Optional per-tool execution timeout.