Tiffany Runtime Model

Tiffany is a coroutine-first agentic runtime built around the idea of deterministic, traceable, yield-driven execution for autonomous system tasks.

May is the exclusive execution substrate. Mayfly provides task and workflow policy above it; see ADR-0033.

Execution Model

• Coroutine Runtime: May runs cooperative stackful coroutines across its workers. No competing executor or reactor may be introduced.
• System Calls: Task policy records semantic waits while May owns the concrete coroutine park, timer, I/O readiness, and wake operation.
• Trampolining: Nested coroutines are managed via a LIFO stack to support function-like composition.
• Replayability: Tasks emit WAL logs with every yield, enabling complete deterministic replay.
• Telemetry: Progress is simultaneously emitted to the PAL stream for real-time observability.

Agents and Isolation

Each agent:

• Operates in a self-contained environment (microVM or Apple Container)
• Loads semantic memory (GraphDB + VectorDB)
• Executes plans via the ReAct loop
• Coordinates with orchestrator over mTLS/gRPC

Diagrams

You can find system-level sequence diagrams in the Diagrams section.