An execution host is the supervisor boundary that owns ACP sessions, agent processes, and execution workspaces. Web Core addresses execution through a durable host and assignment contract instead of treating a URL or filesystem path as ownership.

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Current topology

The supported topology has one active trusted local execution host, loopback HTTP, and shared local storage. There is no supported placement across multiple simultaneous hosts and no mid-turn migration claim today. The host contract already provides:
  • durable host identity across supervisor restarts;
  • monotonically increasing assignment epochs and stale-driver fencing;
  • a durable command ledger and idempotent host receipts;
  • opaque workspace handles on normal session operations;
  • attributable sessions and node attempts.

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Path to multiple supervisors

These boundaries are the prerequisite for a future pool of supervisor hosts. That stage must add remote transport, placement policy, host visibility, and attempt-boundary recovery without weakening fencing or evidence ownership. Until that stage ships, deploy one supervisor per MAIster control plane and follow the single-host deployment guide.