Core concepts
The Counterworld mental model.
A Counterworld world is a running software system whose state changes through agent actions, simulated users and time.
One world, four connected layers
The layers are separate enough to configure independently, but they operate on one shared state. An order created by a simulated buyer is the same order the agent later reads through the API.
Definition and instance are different
A definition describes what the world can contain and how it behaves. An instance is one populated, running realization of that definition.
- Definition
- Versioned systems, schemas, mutations, actor types and evaluators.
- Instance
- Concrete records, identities, event queue, history and current clock.
- Checkpoint
- An immutable reference to an instance at an exact moment.
- Fork
- A new running instance that begins from a checkpoint.
State records what is true. Events record what happened.
State answers questions such as “is this invoice paid?” The event history explains how it became paid, who changed it and which side effects followed.
- State: current entities, relationships, permissions and pending schedules.
- Events: ordered mutations with actor, time, inputs and effects.
- History: coherent prior state and events generated before the agent starts.
Actors and time create work independently of the agent
Simulated buyers, customers, store admins, sales reps, support agents, employees, approvers and operators observe the current world, make decisions and act through the same valid mutations. The clock determines when they react.
Evaluation compares resulting worlds
The primary output is not a response string. It is the world state produced by the agent after other actors and time have responded.
Evaluators can check immediate invariants, delayed consequences and aggregate outcomes such as retention, backlog, margin or policy violations.