diff --git a/packages/agents-audit/src/spec-contract-visibility.test.ts b/packages/agents-audit/src/spec-contract-visibility.test.ts
new file mode 100644
index 0000000..752ba0d
--- /dev/null
+++ b/packages/agents-audit/src/spec-contract-visibility.test.ts
@@ -0,0 +1,98 @@
+import { describe, expect, it } from 'vitest';
+import { validate, validateV4, version } from '@workspacejson/spec';
+import type { CoChangeEntry, FragilityEntry, WorkspaceJsonV4 } from '@workspacejson/spec';
+
+/**
+ * META-244 regression guard: the CLI compiles against the REAL published
+ * `@workspacejson/spec` declarations, not a local copy of them.
+ *
+ * `types/ambient.d.ts` used to carry a handwritten
+ * `declare module '@workspacejson/spec'`. Ambient module declarations win over
+ * node_modules typings, so that stub shadowed the real package — and it omitted
+ * the entire v0.4 contract. Every symbol imported above exists ONLY in the real
+ * published package and was absent from the stub, so **reintroducing the shadow
+ * breaks this file at compile time** (TS2305 / TS2724), not at runtime.
+ *
+ * That is the point: this is a type-visibility test whose primary assertion is
+ * that it compiles at all. The runtime expectations below keep it honest under
+ * a test runner that strips types.
+ */
+describe('@workspacejson/spec contract visibility', () => {
+  it('exposes the published version as a value, not a local guess', () => {
+    // The removed stub declared `version: string`. The real package declares the
+    // literal "0.4.4" — so this also pins which contract we compiled against.
+    expect(version).toBe('0.4.4');
+  });
+
+  it('exposes validateV4, which the removed ambient stub did not declare', () => {
+    expect(validateV4).toBeTypeOf('function');
+  });
+
+  it('accepts a v0.4 artifact through the published validators', () => {
+    // Under the removed stub, `validate` was typed `data is WorkspaceJsonV3`
+    // only. The real declaration is `data is WorkspaceJsonV3 | WorkspaceJsonV4`,
+    // so a v0.4 artifact is a first-class member of the contract here.
+    const artifact: WorkspaceJsonV4 = {
+      manual: {},
+      generated: {
+        specVersion: '0.4',
+        generatedAt: '2026-07-26T00:00:00.000Z',
+        by: { name: 'agents-audit', version: '0.4.4' },
+        frameworkManifest: [],
+        fileIndex: {},
+        coChange: [],
+        fragility: [],
+      },
+      agents: {},
+      health: { intelligenceState: 'INSUFFICIENT_DATA', observationCount: 0, confidence: 0 },
+    };
+
+    expect(artifact.generated.specVersion).toBe('0.4');
+    expect(validate(artifact)).toBe(true);
+    expect(validateV4(artifact)).toBe(true);
+  });
+
+  it('exposes the v0.4 evidence entry types', () => {
+    // CoChangeEntry and FragilityEntry exist only in the real package. Their
+    // shapes are asserted structurally so a silent contract change is visible
+    // here rather than discovered during META-195 producer work.
+    const coChange: CoChangeEntry = {
+      files: ['src/a.ts', 'src/b.ts'],
+      rate: 0.5,
+      occurrences: 2,
+      generated: false,
+    };
+    const fragility: FragilityEntry = {
+      file: 'src/a.ts',
+      changeCount: 10,
+      revertCount: 2,
+      revertRate: 0.2,
+      fragilityScore: 0.4,
+      excluded: false,
+    };
+
+    // Set semantics: exactly two entries, order not meaningful.
+    expect(coChange.files).toHaveLength(2);
+    expect(fragility.revertRate).toBeCloseTo(fragility.revertCount / fragility.changeCount, 5);
+  });
+
+  it('still narrows v0.3 artifacts, so the migration contract is unchanged', () => {
+    // Guards against the opposite failure: consuming real types must not have
+    // widened or broken v0.3 handling, which the producer emits today.
+    const v3 = {
+      manual: {},
+      generated: {
+        specVersion: '0.3',
+        generatedAt: '2026-07-26T00:00:00.000Z',
+        by: { name: 'agents-audit', version: '0.4.4' },
+        frameworkManifest: [],
+        fileIndex: {},
+      },
+      agents: {},
+      health: { intelligenceState: 'INSUFFICIENT_DATA', observationCount: 0, confidence: 0 },
+    };
+
+    expect(validate(v3)).toBe(true);
+    expect(validateV4(v3)).toBe(false);
+  });
+});
diff --git a/scripts/check-architecture.mjs b/scripts/check-architecture.mjs
index 384475e..e715761 100644
--- a/scripts/check-architecture.mjs
+++ b/scripts/check-architecture.mjs
@@ -90,6 +90,34 @@ for (const file of sourceFiles) {
   }
 }
 
+// ---------------------------------------------------------------------------
+// 2b. No ambient re-declaration of a standard-owned package (META-244).
+//
+// Ambient module declarations win over node_modules typings, so a handwritten
+// `declare module '@workspacejson/spec'` silently shadows the real published
+// contract — this repository shipped exactly that until META-244, and it hid
+// the entire v0.4 surface from the compiler. workspacejson/standard owns those
+// types; consume them, never restate them.
+// ---------------------------------------------------------------------------
+const AMBIENT_FIRST_PARTY = /declare\s+module\s+['"]@workspacejson\/[^'"]+['"]/;
+
+// Comments are stripped first: this rule is about what the compiler sees, and
+// the note in types/ambient.d.ts explaining why the shadow was removed
+// necessarily quotes the very syntax it forbids.
+function stripComments(source) {
+  return source.replace(/\/\*[\s\S]*?\*\//g, "").replace(/^[ \t]*\/\/.*$/gm, "");
+}
+
+for (const file of sourceFiles) {
+  if (SELF_REFERENTIAL.has(file)) continue;
+  if (!file.endsWith(".d.ts")) continue;
+  const match = stripComments(readFileSync(file, "utf8")).match(AMBIENT_FIRST_PARTY);
+  if (match) {
+    report("shadowed-standard-types", file,
+      `${match[0]} re-declares a standard-owned contract; consume the published declarations instead (META-244)`);
+  }
+}
+
 // ---------------------------------------------------------------------------
 // 3. No host-integration or site implementation in the CLI repository.
 // ---------------------------------------------------------------------------
diff --git a/scripts/check-architecture.test.mjs b/scripts/check-architecture.test.mjs
index ffccdeb..b88257f 100644
--- a/scripts/check-architecture.test.mjs
+++ b/scripts/check-architecture.test.mjs
@@ -48,6 +48,19 @@ const cases = [
       properties: { manual: { type: "object" }, generated: { type: "object" } },
     }, null, 2)),
   },
+  {
+    name: "shadowed-standard-types: ambient re-declaration of @workspacejson/spec",
+    expect: "shadowed-standard-types",
+    mutate: (root) => write(join(root, "types/ambient.d.ts"),
+      readFileSync(join(root, "types/ambient.d.ts"), "utf8")
+      + `\ndeclare module '@workspacejson/spec' {\n  export const version: string;\n}\n`),
+  },
+  {
+    name: "shadowed-standard-types: ambient re-declaration of @workspacejson/rules",
+    expect: "shadowed-standard-types",
+    mutate: (root) => write(join(root, "types/rogue.d.ts"),
+      `declare module "@workspacejson/rules" {\n  export type Finding = unknown;\n}\n`),
+  },
   {
     name: "repository-boundary: host-integration code in the CLI repo",
     expect: "repository-boundary",
diff --git a/types/ambient.d.ts b/types/ambient.d.ts
index 7557921..19c3bdd 100644
--- a/types/ambient.d.ts
+++ b/types/ambient.d.ts
@@ -83,112 +83,18 @@ declare module 'commander' {
   }
 }
 
-declare module '@workspacejson/spec' {
-  export const workspaceJsonSchema: {
-    readonly $schema: string;
-    readonly $id: string;
-    readonly title: string;
-    readonly type: string;
-    readonly required: readonly string[];
-    readonly additionalProperties: boolean;
-    readonly properties: Record<string, unknown>;
-  };
-
-  export const version: string;
-
-  export function validate(data: unknown): data is WorkspaceJsonV3;
-  export function validateLegacy(data: unknown): boolean;
-
-  export interface WorkspacePackage {
-    name?: string;
-    path: string;
-    agentsMd?: string;
-    dependencies?: string[];
-    [key: string]: unknown;
-  }
-
-  export interface WorkspaceConvention {
-    raw: string;
-    type: 'filename-case' | 'directory-layout' | 'naming' | 'structural' | 'other';
-    canonical: string;
-  }
-
-  export interface WorkspaceAgentFiles {
-    agentsMd?: string;
-    workspaceJson?: string;
-  }
-
-  export interface WorkspaceGitSummary {
-    nonAgentsCommitCount30Days: number;
-    filesChangedLast30Days: string[];
-  }
-
-  export interface WorkspaceHygiene {
-    score: number;
-    grade: 'A' | 'B' | 'C' | 'D' | 'F';
-    failCount: number;
-    warnCount: number;
-    scannedAt: string;
-  }
-
-  export interface WorkspaceJson {
-    version: string;
-    generatedAt?: string;
-    repository?: string;
-    topology?: 'single-package' | 'monorepo' | 'polyglot-monorepo';
-    ciProvider?: 'github-actions' | 'gitlab-ci' | 'circleci' | 'jenkins' | 'none' | 'unknown';
-    agentFiles?: WorkspaceAgentFiles;
-    frameworks?: string[];
-    conventions?: WorkspaceConvention[];
-    packages?: WorkspacePackage[];
-    gitSummary?: WorkspaceGitSummary;
-    hygiene?: WorkspaceHygiene;
-    metadata?: Record<string, unknown>;
-    [key: string]: unknown;
-  }
-
-  export interface FrameworkEntry {
-    name: string;
-    version?: string;
-    confidence: number;
-  }
-
-  export interface FileIndexEntry {
-    fragility?: number;
-    aiModificationCount?: number;
-    humanModificationCount?: number;
-    [key: string]: unknown;
-  }
-
-  export type IntelligenceState = 'INSUFFICIENT_DATA' | 'OBSERVING' | 'CONFIDENT';
-
-  export interface WorkspaceJsonV3 {
-    manual: {
-      fragileFiles?: Array<{ path: string; reason?: string }>;
-      coChangePatterns?: Array<{ files: string[]; note?: string }>;
-      [key: string]: unknown;
-    };
-    generated: {
-      specVersion: '0.3';
-      generatedAt: string;
-      by: { name: string; version: string };
-      frameworkManifest: FrameworkEntry[];
-      fileIndex: Record<string, FileIndexEntry>;
-      topology?: { packageCount?: number; [key: string]: unknown };
-      warnings?: string[];
-      [key: string]: unknown;
-    };
-    agents: Record<string, unknown>;
-    health: {
-      intelligenceState: IntelligenceState;
-      observationCount: number;
-      confidence: number;
-      averageFragility?: number;
-      fragileFileCount?: number;
-      [key: string]: unknown;
-    };
-  }
-}
+// The `@workspacejson/spec` contract is NOT declared here.
+//
+// It previously was: a handwritten `declare module '@workspacejson/spec'`
+// restating that package's type surface. Ambient module declarations win over
+// node_modules typings, so the stub shadowed the real published declarations
+// even though the dependency is a registry-backed pin — and it silently hid the
+// entire v0.4 contract (WorkspaceJsonV4, validateV4, CoChangeEntry,
+// FragilityEntry) from this repository's compiler.
+//
+// workspacejson/standard owns that contract. This repository consumes the real
+// published declarations and must not keep a second editable copy (META-244,
+// enforcing META-165). scripts/check-architecture.mjs rejects reintroduction.
 
 declare module 'ora' {
   export interface Spinner {