# Product guarantees

These invariants define the end-product contract across languages, providers,
runtimes, deployment targets, and interfaces. A selected profile's exact
support claims and applicable evidence establish which capabilities are
available; this list does not establish implementation support by itself.

## Meaning and ownership

- Every stable identity and contract has one semantic owner.
- Cross-system consumers use public owned records, never sibling internals.
- Authored syntax is a projection; normalized owner meaning is not coupled to
  tokens, field order, parser trees, or implementation-language bodies.
- Independent domains retain their own namespaces and compose through explicit
  directional mappings.
- Every One-owned source form, imported name, trait application, generated
  symbol, command, and owner record resolves to an exact snapshot-bound
  definition or an explicit unavailable/stale result.

## Closure and selection

- Every root receives an independently computed semantic, implementation,
  provider, schema, codec, artifact, resource, permission, and Build closure.
- Only explicit reachable edges activate optional contributions.
- Workspace membership, package installation, Cargo features, generated files,
  and available providers never create semantic activation.
- Planning is deterministic for the same exact inputs and records every
  inclusion, alternative, conflict, and cost.

## Stage separation

- Requirements are not grants.
- Declarations are not implementations.
- Implementation claims are not selections.
- Selections are not artifacts.
- Selected provider profiles are not provider realization receipts.
- Artifact bytes are not Build evidence.
- Plans and approvals are not mutation authority.
- Provider acknowledgement is not semantic convergence.
- Observations and historical assertions retain their provenance and do not
  become truth merely because they were recorded.

## Authority and effects

- A grant can satisfy or narrow a requirement; it cannot widen one.
- Runtime tokens are attenuated, expiring, scoped to exact subjects, and
  validated at the real enforcement boundary.
- Secret values remain outside source, locks, plans, artifacts, diagnostics,
  histories, and generated projections.
- Every consequential external effect retains intent, authorization, attempt,
  fence, dispatch, acknowledgement, observation, and reconciliation as
  applicable.
- An outcome that may have crossed its boundary remains unknown until safely
  reconciled.

## Build and supply chain

- Build consumes a locked physical selection without reselecting.
- Every artifact retains its complete action, source, toolchain, dependency,
  target, provenance, and verification closure.
- Generated projections are disposable; the source contract and projection
  receipt remain authoritative.
- First-party and third-party tools and providers cross the same claim-scoped
  admission boundary.
- Dependency and toolchain demands retain their exact consumer, role, source,
  constraint, resolution envelope, provenance, and private-workspace
  projection; deduplicated bytes grant no reachability.

## Deployment and recovery

- Apply starts or resumes one immutable reviewed operation.
- Desired state, observed state, provider application, and verified
  postconditions remain distinct.
- Rollout, rollback, restore, failover, migration, compensation, and deletion
  are forward plans with their own authority and evidence.
- External history is never rewritten to simulate reversal.

## Inspection and automation

- Every meaningful decision resolves to an inspectable owner record and proof
  path, subject to declared retention and erasure policy.
- Missing, stale, unresolved, unsupported, and unsatisfied states are typed and
  visible; no interface invents a value from weaker evidence.
- Human, SDK, automation, MCP, and agent interfaces project the same public
  operations and cannot bypass the lifecycle.
- End-user product surfaces describe user work and outcomes; deliberate
  evidence views expose architecture and operational proof.

## Example

An illustrative unsupported target remains explicit instead of falling back:

```json
{
  "kind": "unsatisfied",
  "requirement": "durable transactional state",
  "root": "parcelhub#OrdersApi@1",
  "eligible_realizations": []
}
```

Normative source:
[repository architecture](https://github.com/muijf/one/blob/main/AGENTS.md).