Architecture

The runtime is split by actual execution boundary rather than by organizational role.

Planes

• Chat Runtime: provider adapters, composers, streams, messages, attachments.
• ScriptCat: router, Mother Script, registry, mutation, target selection, agent tabs.
• Torsion Node: local IPC, journal, files, processes, artifacts, identity, optional peer transport.
• Participant Edge: optional participant-owned persistent endpoint and encrypted buffer.

One operation

origin → Router → provider adapter → target effect
       → observed postcondition → evidence → origin

Durable operation, agent, endpoint, and artifact identities are not browser tab IDs. Transport can restart while logical work survives.

Specification §4 →