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+---
+id: MASON-WP-0010
+type: workplan
+title: "Materialize SecurityCases from their type, with acceptance as the only gate"
+domain: infotech
+repo: ops-mason
+status: ready
+flavor: implementation
+owner: claude-code
+topic_slug: netkingdom
+created: "2026-10-08"
+updated: "2026-10-08"
+depends_on: []
+related_repos:
+  - net-kingdom
+  - ops-warden
+  - railiance-platform
+---
+
+# MASON-WP-0010 — Materialize SecurityCases from their type, with acceptance as the only gate
+
+## Why
+
+NetKingdom is introducing SecurityCaseTypes (net-kingdom `NK-WP-0048`, canon
+`security-case-types_v0.1`, proposed). A type is designed once, with
+documentation, tests and an informed-decision. Each case of an implemented type
+is then light: it is accepted, ops-mason arranges it, and ops-warden follows
+through.
+
+ops-mason's four phases (construction plan, review, executive summary, build)
+stay exactly as they are for **new types and for structure that no type
+covers**. For a **KnownSecurityCase**, the construction plan is rendered from
+the type's materialization templates, and the executive-summary gate collapses
+to the case acceptance, because the shape was decided when the type was
+acknowledged.
+
+MASON-WP-0009 (a hand-built placement of a key-cape client secret) is the kind
+of work this replaces. It becomes a reference instance for the first type.
+
+## Tasks
+
+```task
+id: MASON-WP-0010-T01
+status: wait
+depends_on: [NK-WP-0048-T03]
+blocking_reason: "The materialization section follows the type schema and template."
+priority: high
+```
+
+### T01 — Define the type's materialization section
+
+Propose the `materialization` part of the SecurityCaseType schema together with
+net-kingdom: policy, role, KV path structure and catalog-entry templates over
+case parameters, with naming rules. These must respect ops-mason's existing
+"respect, extend or compact before adding" review, so that a type cannot
+template sprawl. Write it for the first type, `oidc-browser-relying-party`, from
+MASON-WP-0009 and the existing key-cape client custody paths.
+
+```task
+id: MASON-WP-0010-T02
+status: wait
+depends_on: [MASON-WP-0010-T01]
+blocking_reason: "Rendering needs the agreed materialization section."
+priority: high
+```
+
+### T02 — Render a construction plan from a case
+
+`mason plan --case <case.yaml>` validates the case against its `implemented`
+type, renders the construction plan from the type's templates, and runs the
+existing consistency review against current OpenBao structure (read-only, no
+values). The output is the usual plan, marked `derived-from-type`, plus the
+case-acceptance reference in place of a fresh executive summary.
+
+Tests: render the reference case; refuse a case whose type is not
+`implemented`; refuse parameter values outside the type's validation; flag a
+collision with existing structure.
+
+```task
+id: MASON-WP-0010-T03
+status: wait
+depends_on: [MASON-WP-0010-T02]
+blocking_reason: "Building from an accepted case follows the rendering."
+priority: high
+```
+
+### T03 — Build from an accepted case
+
+`mason build --case <case.yaml>` builds a rendered plan when the case's
+acceptance record is present, with no separate executive-summary approval. Its
+audit trail names the case, the type version and the acceptance. It proposes the
+pointer-only ops-warden catalog entries the type defines, as today. Rollback
+removes exactly what this case created.
+
+Acceptance: the Forgejo reference case (NK-WP-0048-T06) materializes through this
+path.
+
+```task
+id: MASON-WP-0010-T04
+status: wait
+depends_on: [MASON-WP-0010-T03]
+blocking_reason: "Adoption follows a working light path."
+priority: medium
+```
+
+### T04 — Adopt MASON-WP-0009 as a case
+
+Once `oidc-browser-relying-party` (or the confidential service client type) is
+implemented, express MASON-WP-0009's placement as a case of that type without
+changing the live structure, and close the hand-built path.