Module brain 

The conversation decision-maker seam.

The embedder implements AgentBrain over its own engine; flowcat-core ships a demo brain. The brain owns the system prompt + tool set for the current state and decides what a tool call means (see DESIGN.md “Trait contracts”).

BrainAction and ToolDecl are defined in crate::types (the shared data-type module) and re-exported here, which is their contract location.

Re-exports

pub use crate::types::BrainAction;

pub use crate::types::ToolDecl;

Traits

AgentBrain

Drives the conversation: provides the active prompt + tools, interprets tool calls into BrainActions, and reports completion + collected variables.