diff --git a/apps/desktop/src/check-packaging-contract.ts b/apps/desktop/src/check-packaging-contract.ts
index 2f6dc61a..e7a4930d 100644
--- a/apps/desktop/src/check-packaging-contract.ts
+++ b/apps/desktop/src/check-packaging-contract.ts
@@ -12,6 +12,7 @@ const appDir = dirname(distDir);
 const repoRoot = resolve(appDir, "../..");
 const packageJson = JSON.parse(readFileSync(join(appDir, "package.json"), "utf8")) as { scripts?: Record<string, string>; dependencies?: Record<string, string>; devDependencies?: Record<string, string>; description?: string; author?: string };
 const rootPackageJson = JSON.parse(readFileSync(join(repoRoot, "package.json"), "utf8")) as { scripts?: Record<string, string> };
+const workspaceConfig = readFileSync(join(repoRoot, "pnpm-workspace.yaml"), "utf8");
 const builderConfigPath = join(appDir, "electron-builder.yml");
 const builderConfig = readFileSync(builderConfigPath, "utf8");
 
@@ -27,6 +28,10 @@ assert.equal(packageJson.dependencies?.["@open-pets/cursor"], "workspace:*");
 assert.equal(packageJson.dependencies?.["@open-pets/mcp"], "workspace:*");
 assert.equal(packageJson.dependencies?.["@open-pets/opencode"], "workspace:*");
 assert.equal(packageJson.dependencies?.["@open-pets/agent-events"], "workspace:*");
+assert.equal(packageJson.dependencies?.["@img/sharp-win32-x64"], undefined, "sharp platform binaries must stay optional transitive deps, not direct host-breaking dependencies.");
+assert.match(workspaceConfig, /supportedArchitectures:[\s\S]*?os:[\s\S]*?- darwin[\s\S]*?- win32[\s\S]*?- linux/, "pnpm must install optional sharp binaries for desktop release OS targets.");
+assert.match(workspaceConfig, /supportedArchitectures:[\s\S]*?cpu:[\s\S]*?- x64[\s\S]*?- arm64/, "pnpm must install optional sharp binaries for desktop release CPU targets.");
+assert.match(workspaceConfig, /supportedArchitectures:[\s\S]*?libc:[\s\S]*?- glibc/, "pnpm must install optional sharp binaries for Linux glibc release targets.");
 assert.match(packageJson.devDependencies?.["electron-builder"] ?? "", /^\^26\.(?:9|[1-9]\d)\./, "desktop AppImage packaging must use electron-builder 26.9+ for conditional Linux sandbox handling.");
 assert.match(builderConfig, /appId:\s*dev\.openpets\.app/);
 assert.match(builderConfig, /productName:\s*OpenPets/);
@@ -277,6 +282,10 @@ function checkPackageOutput(): void {
   assert.ok(existsSync(join(appContents, "node_modules", "yauzl", "fd-slicer.js")), "packaged yauzl fd-slicer helper is missing.");
   assert.ok(existsSync(join(appContents, "node_modules", "buffer-crc32", "index.js")), "packaged yauzl transitive dependency buffer-crc32 is missing.");
   assert.ok(existsSync(join(appContents, "node_modules", "pend", "index.js")), "packaged yauzl transitive dependency pend is missing.");
+  assert.ok(existsSync(join(appContents, "node_modules", "sharp", "lib", "index.js")), "packaged sharp runtime is missing.");
+  assert.ok(existsSync(join(appContents, "node_modules", "@img", "sharp-win32-x64", "lib", "sharp-win32-x64.node")), "packaged Windows x64 sharp native binary is missing.");
+  assert.ok(existsSync(join(appContents, "node_modules", "@img", "sharp-linux-x64", "lib", "sharp-linux-x64.node")), "packaged Linux x64 sharp native binary is missing.");
+  assert.ok(existsSync(join(appContents, "node_modules", "@img", "sharp-darwin-x64", "lib", "sharp-darwin-x64.node")), "packaged macOS x64 sharp native binary is missing.");
   assertRegularNonSymlink(join(appContents, "node_modules", "@open-pets", "mcp", "dist", "index.js"));
   assertRegularNonSymlink(join(appContents, "node_modules", "@open-pets", "cli", "dist", "index.js"));
   assertRegularNonSymlink(join(appContents, "node_modules", "@open-pets", "opencode", "dist", "plugin.js"));
diff --git a/pnpm-workspace.yaml b/pnpm-workspace.yaml
index d190a089..6cc7c76a 100644
--- a/pnpm-workspace.yaml
+++ b/pnpm-workspace.yaml
@@ -1,6 +1,16 @@
 packages:
   - "apps/*"
   - "packages/*"
+supportedArchitectures:
+  os:
+    - darwin
+    - win32
+    - linux
+  cpu:
+    - x64
+    - arm64
+  libc:
+    - glibc
 allowBuilds:
   electron-winstaller: false
   sharp: true