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+# ADR 0001 — Workstation and Execution Contract Boundaries
+
+**Date:** 2026-04-14  
+**Status:** `Proposed`
+
+---
+
+## Context
+
+SourceOS has two related but distinct needs:
+
+1. A canonical typed contract layer for the execution fabric: agent sessions, execution decisions, telemetry, provenance, release receipts, and policy-bound execution surfaces.
+2. A reproducible workstation profile for developer/operator environments on GNOME/CoreOS/Silverblue-derived systems, including package manifests, desktop defaults, launcher actions, and input remapping.
+
+Recent design work also clarified additional execution-layer concepts that are not yet first-class types in this repository:
+
+- **Run Capsule** — immutable, signed record of one agent execution, including inputs, outputs, tool calls, decisions, and ledger state.
+- **Agent Contract** — declarative description of an agent’s tools, policies, deployment profiles, and audit requirements.
+
+The risk is that workstation/profile work lands as ad hoc shell scripts while execution-fabric work lands separately, producing drift between:
+
+- what an agent is declared to be allowed to do,
+- what the workstation exposes as launcher/actions/tools,
+- and what the audit/provenance layer records.
+
+## Decision
+
+We will treat both execution-fabric objects and workstation-profile objects as first-class typed contracts in `sourceos-spec`, but we will phase them differently.
+
+### Phase 1 — ADR + RFC first
+
+Before adding schemas, we record the architectural boundary:
+
+- **Execution contracts** define what an agent/session/run may do and what must be recorded.
+- **Workstation contracts** define what a workstation profile installs, configures, and exposes to users/operators.
+
+### Phase 2 — Additive schema families
+
+We will add the following types as additive contracts once field definitions stabilize:
+
+#### Execution-facing types
+
+- `RunCapsule`
+- `AgentContract`
+
+#### Workstation-facing types
+
+- `WorkstationProfile`
+- `PackageManifest`
+- `DesktopProfile`
+- `LauncherAction`
+- `LauncherProvider`
+
+### Contract boundary rule
+
+Workstation-facing types must not redefine execution/audit semantics already owned by execution-facing contracts.
+
+Specifically:
+
+- `WorkstationProfile` may reference `AgentContract`, but does not embed policy logic in an incompatible form.
+- `LauncherAction` may reference execution surfaces/capabilities, but audit/provenance requirements remain owned by execution contracts such as `RunCapsule`, `ExecutionDecision`, and related receipts.
+- Desktop/launcher affordances are a presentation/configuration layer over the canonical capability and audit plane, not a parallel authority system.
+
+## Alternatives considered
+
+| Alternative | Reason not chosen |
+|-------------|------------------|
+| Keep workstation profile work only in build/config repos with no typed contract | Rejected because it creates drift and weakens policy/audit interoperability |
+| Add all new schemas immediately | Rejected because the field model is not yet stable enough and would likely cause churn |
+| Keep execution contracts in one repo and workstation contracts in a separate spec repo | Rejected because the contract boundary between launcher/desktop actions and audited execution would become harder to govern |
+
+## Consequences
+
+### Positive
+
+- Keeps `sourceos-spec` as the canonical contract home for both audited execution and workstation profile semantics.
+- Prevents launcher/desktop integrations from becoming undocumented side channels.
+- Provides a clean path for GNOME/Albert/Kinto/Fusuma integration to reference the same capability and audit model as the broader SourceOS execution fabric.
+- Allows build/config repos in `SociOS-Linux` to remain implementation-focused while `SourceOS-Linux/sourceos-spec` remains contract-focused.
+
+### Negative
+
+- Introduces more schema surface area that will need careful versioning and examples.
+- Requires discipline to avoid over-modeling early design details.
+- Forces workstation profile work to meet the same compatibility rigor as the rest of the contract layer.
+
+## References
+
+- `SourceOS-Linux/sourceos-spec/README.md`
+- `SourceOS-Linux/sourceos-spec/CONTRIBUTING.md`
+- `SociOS-Linux/enhancements/workstation/sourceos_workstation_profile_v0.md`