Sub-Agents

` Parent Agent ├── prompt("Research X and implement Y") │ ├── calls SubAgentTool("researcher", task="Research X") │ │ └── child agent_loop() with read/search tools → returns findings │ ├── calls SubAgentTool("coder", task="Implement Y based on findings") │ │ └── child agent_loop() with edit/write tools → returns result │ └── summarizes both results ` Each sub-agent invocation starts a fresh conversation — no state leaks between calls.

Sub-agents let a parent agent delegate tasks to child agent loops, each with their own system prompt, tools, and provider. The parent LLM invokes them like any other tool.

`rust use std::sync::Arc; use yoagent::sub_agent::SubAgentTool; use yoagent::provider::AnthropicProvider; use yoagent::tools; let researcher = SubAgentTool::new("researcher", Arc::new(AnthropicProvider)) .with_description("Searches and reads files to gather information.") .with_system_prompt("You are a research assistant. Be thorough and concise.") .with_model("claude-sonnet-4-20250514") .with_api_key(&api_key) .with_tools(vec![ Arc::new(tools::ReadFileTool::new()), Arc::new(tools::SearchTool::new()), ]) .with_max_turns(10); `

`rust use yoagent::agent::Agent; let mut agent = Agent::new(AnthropicProvider) .with_system_prompt("You coordinate between sub-agents.") .with_model("claude-sonnet-4-20250514") .with_api_key(api_key) .with_sub_agent(researcher) .with_sub_agent(coder); ` The parent sees sub-agents as regular tools. It decides when to delegate based on its system prompt.