# YSD-0131 — Private/local model execution and residency requirements

- **Status:** approved (2026-07-18)
- **Priority:** P0 EXT — blocking (production rollout gated via YSD-0139)
- **Decision owner:** @GreyChimp
- **Drafted:** 2026-07-18 by Claude Code (claude-fable-5)
- **Approval:** approved as recommended by @GreyChimp on 2026-07-18; outcome
  recorded in decision-log.json; review by 2027-07-18

## Question

What are the private/local model execution, data-residency, offline, and
provider-substitution requirements?

## Recommendation

All model inference routes through the Isis gateway with provider substitution
(open-model registry + RunPod endpoints per the 2026-07-06 migration); study
sources never leave the tenant's storage region for inference unless the grant
explicitly allows it; offline/no-model operation is a first-class mode
(YSD-0018/YSD-1039) — manual study must be complete without any model;
enterprise residency requirements (local or private endpoints) are declared per
tenant and enforced by the gateway configuration, failing closed to manual mode.

## Options considered

- Direct provider SDK calls from workspace code — rejected: bypasses YSD-0160
  gateway ownership and audit.
- Mandatory local models — rejected: no on-box GPU; RunPod endpoints are the
  execution substrate.

## Consequences

- Isis adapter (Section 6) carries residency/substitution config; degraded-mode
  UX follows YSD-2007.

## Machine-enforced outcome (once approved)

Architecture tests (YSD-0164) reject unapproved model calls; gateway config
schema validates residency settings.