--title=Actor model: BECOME primitive

Implement the BECOME primitive for changing actor behavior.

Overview

This is Phase 3 of the actor-native agent orchestration system. BECOME allows an actor to change how it responds to the next message it receives.

Requirements

Become Tool

Add a become tool to the agent toolset:

become:
  description: Change your behavior for the next message you receive
  parameters:
    prompt: New system prompt or instructions (required)
    tools: New tool whitelist (optional, defaults to current)
    context: Additional context to carry forward (optional)
    reason: Why you're changing behavior (for logging)

Behavior State

• Store current behavior in actor state file
• Behavior = system prompt + tool whitelist + context
• On next message, load behavior from state

Behavior Changes

BECOME does NOT change:

• Actor identity (actor_id stays the same)
• Capabilities (can't expand via BECOME)
• Customer relationships

BECOME DOES change:

• System prompt for next message
• Which tools are active (within capability limits)
• Context/state carried forward

Use Cases

• State machines: planning -> implementing -> reviewing
• Iteration: process_item -> process_item -> done
• Focus shift: "now review what you wrote"

Implementation Notes

Files to modify/create

• Omni/Agent/Actor.hs - BECOME implementation, behavior state
• Omni/Agent/Tools.hs - Add become tool
• Omni/Agent/Engine.hs - Load behavior on message receipt

State Storage

• _/actors/{actor_id}/behavior.json - current behavior
• Updated when BECOME is called
• Read at start of each message processing

Testing

• Test behavior persists across messages
• Test tool whitelist change works
• Test capabilities still enforced after BECOME
• Test context carried forward

Dependencies

• Task: Actor model: Message passing infrastructure (messages trigger behavior)
• Task: Actor model: CREATE primitive (actor state infrastructure)

References

• Spec: _/llm/actors.md (BECOME primitive, Behaviors section)