Architecture

HICA is designed around a transparent, event-sourced workflow with three pillars:

• Agent: orchestrates LLM calls, tool selection, parameter filling, and execution.
• Tools: local Python tools and remote MCP tools with a unified ToolRegistry.
• Thread: append-only event log capturing every step for auditability and resumability.

Agent flow

1. Select intent (a tool name, done, or clarification).
2. Fill parameters for the selected tool.
3. Execute the tool and add a tool_response event.
4. Repeat until done.

Thread and events

Each interaction is recorded as an event:

• user_input, llm_response, tool_call, tool_response, clarification, final_response

This enables pause/resume, reproducibility, and full observability of the agent’s decisions.

Tool results

Tools return:

ToolResult(
  llm_content: str,
  display_content: str,
  raw_result: Any,
)

This separates machine-optimized content for the LLM from human-friendly output.