Architecture & security
Constal limits authority with immutable identity, explicit boundaries, and least-privilege execution.
Authority boundaries
| Concern | Guarantee |
|---|---|
| Agents and Channels | Execute one pinned immutable revision |
| Sessions and Runs | Preserve ordered work and durable history |
| Resources | Expose only declared operations allowed by Policy |
| Credentials | Remain encrypted and unavailable to Agent code |
| Analytics | Observe workflows without becoming workflow authority |
| Sandboxes | Isolate code and restrict external access |
Security invariants
- Agent and Channel code receives no ambient privileged storage, secret, analytics, or provider authority.
- Identity is normalized before execution; Agent code sees only safe customer references.
- Deployments, Policies, Resources, and Tools are pinned into Run authority.
- Every external operation crosses authorization, durable recording, and effect-aware recovery.
- Credential material is supplied only to the authorized integration that consumes it.
Determinism and failure
Canonical hashes bind accepted definitions and inputs to exact semantics. Stale execution cannot change acknowledged truth. Direct nondeterminism and arbitrary network access are denied in managed execution; use journaled Resource operations. Stable SDK errors distinguish Policy failure, unknown outcome, lost execution, invalid binding, and related recovery cases.