diff --git a/packages/appkit/src/plugins/agents/agents.ts b/packages/appkit/src/plugins/agents/agents.ts
index 6f755462d..c3e9cbfd2 100644
--- a/packages/appkit/src/plugins/agents/agents.ts
+++ b/packages/appkit/src/plugins/agents/agents.ts
@@ -52,7 +52,7 @@ import type {
 import { isToolkitEntry } from "../../core/agent/types";
 import { createLogger } from "../../logging/logger";
 import { Plugin, toPlugin } from "../../plugin";
-import type { PluginManifest } from "../../registry";
+import { defineManifest } from "../../registry";
 import { agentStreamDefaults } from "./defaults";
 import { EventChannel } from "./event-channel";
 import { AgentEventTranslator } from "./event-translator";
@@ -142,11 +142,7 @@ interface RunState {
 }
 
 export class AgentsPlugin extends Plugin implements ToolProvider {
-  // Routed through `unknown`: the optional resources have differing `fields`
-  // keys (serving `name`, experiment `experimentId`), which TS widens to an
-  // incompatible union on the JSON import. The shape is validated at runtime
-  // against the plugin-manifest schema.
-  static manifest = manifest as unknown as PluginManifest;
+  static manifest = defineManifest(manifest);
   static phase: PluginPhase = "deferred";
 
   declare protected config: AgentsPluginConfig;
diff --git a/packages/appkit/src/plugins/analytics/analytics.ts b/packages/appkit/src/plugins/analytics/analytics.ts
index 782ac33c4..dc3543be4 100644
--- a/packages/appkit/src/plugins/analytics/analytics.ts
+++ b/packages/appkit/src/plugins/analytics/analytics.ts
@@ -27,7 +27,7 @@ import { assertReadOnlySql } from "../../core/agent/tools/sql-policy";
 import { AppKitError, ExecutionError } from "../../errors";
 import { createLogger } from "../../logging/logger";
 import { Plugin, toPlugin } from "../../plugin";
-import type { PluginManifest } from "../../registry";
+import { defineManifest } from "../../registry";
 import type { WorkspaceClient } from "../../workspace-client";
 import { queryDefaults } from "./defaults";
 import manifest from "./manifest.json";
@@ -110,7 +110,7 @@ async function* streamCallbacks<T>(
 
 export class AnalyticsPlugin extends Plugin implements ToolProvider {
   /** Plugin manifest declaring metadata and resource requirements */
-  static manifest = manifest as PluginManifest<"analytics">;
+  static manifest = defineManifest<"analytics">(manifest);
 
   protected static description = "Analytics plugin for data analysis";
   declare protected config: IAnalyticsConfig;
diff --git a/packages/appkit/src/plugins/files/plugin.ts b/packages/appkit/src/plugins/files/plugin.ts
index b770616c4..a8b1c467a 100644
--- a/packages/appkit/src/plugins/files/plugin.ts
+++ b/packages/appkit/src/plugins/files/plugin.ts
@@ -37,8 +37,8 @@ import {
 import { AuthenticationError } from "../../errors";
 import { createLogger } from "../../logging/logger";
 import { Plugin, toPlugin } from "../../plugin";
-import type { PluginManifest, ResourceRequirement } from "../../registry";
-import { ResourceType } from "../../registry";
+import type { ResourceRequirement } from "../../registry";
+import { defineManifest, ResourceType } from "../../registry";
 import { ApiError } from "../../workspace-client";
 import {
   FILES_DOWNLOAD_DEFAULTS,
@@ -69,7 +69,7 @@ export class FilesPlugin extends Plugin implements ToolProvider {
   name = "files";
 
   /** Plugin manifest declaring metadata and resource requirements. */
-  static manifest = manifest as PluginManifest;
+  static manifest = defineManifest(manifest);
   protected static description = "Files plugin for Databricks file operations";
   declare protected config: IFilesConfig;
 
diff --git a/packages/appkit/src/plugins/genie/genie.ts b/packages/appkit/src/plugins/genie/genie.ts
index 845d715ee..351d3988e 100644
--- a/packages/appkit/src/plugins/genie/genie.ts
+++ b/packages/appkit/src/plugins/genie/genie.ts
@@ -20,7 +20,7 @@ import {
 } from "../../core/agent/tools/define-tool";
 import { createLogger } from "../../logging";
 import { Plugin, toPlugin } from "../../plugin";
-import type { PluginManifest } from "../../registry";
+import { defineManifest } from "../../registry";
 import { genieStreamDefaults } from "./defaults";
 import manifest from "./manifest.json";
 import type {
@@ -33,7 +33,7 @@ import type {
 const logger = createLogger("genie");
 
 export class GeniePlugin extends Plugin implements ToolProvider {
-  static manifest = manifest as PluginManifest<"genie">;
+  static manifest = defineManifest<"genie">(manifest);
 
   protected static description =
     "AI/BI Genie space integration for natural language data queries";
diff --git a/packages/appkit/src/plugins/jobs/plugin.ts b/packages/appkit/src/plugins/jobs/plugin.ts
index 4945b5741..1f2cefa02 100644
--- a/packages/appkit/src/plugins/jobs/plugin.ts
+++ b/packages/appkit/src/plugins/jobs/plugin.ts
@@ -14,8 +14,8 @@ import { ExecutionError, ValidationError } from "../../errors";
 import { createLogger } from "../../logging/logger";
 import type { ExecutionResult } from "../../plugin";
 import { Plugin, toPlugin } from "../../plugin";
-import type { PluginManifest, ResourceRequirement } from "../../registry";
-import { ResourceType } from "../../registry";
+import type { ResourceRequirement } from "../../registry";
+import { defineManifest, ResourceType } from "../../registry";
 import type { jobs as jobsTypes } from "../../workspace-client";
 import {
   JOBS_READ_DEFAULTS,
@@ -85,7 +85,7 @@ function abortableSleep(ms: number, signal?: AbortSignal): Promise<void> {
 }
 
 class JobsPlugin extends Plugin {
-  static manifest = manifest as PluginManifest;
+  static manifest = defineManifest(manifest);
 
   declare protected config: IJobsConfig;
   private connector: JobsConnector;
diff --git a/packages/appkit/src/plugins/lakebase/lakebase.ts b/packages/appkit/src/plugins/lakebase/lakebase.ts
index 42b383df2..8518b3ab2 100644
--- a/packages/appkit/src/plugins/lakebase/lakebase.ts
+++ b/packages/appkit/src/plugins/lakebase/lakebase.ts
@@ -23,7 +23,7 @@ import {
 import { assertReadOnlySql } from "../../core/agent/tools/sql-policy";
 import { createLogger } from "../../logging/logger";
 import { Plugin, toPlugin } from "../../plugin";
-import type { PluginManifest } from "../../registry";
+import { defineManifest } from "../../registry";
 import { createWorkspaceClient } from "../../workspace-client";
 import manifest from "./manifest.json";
 import type { ILakebaseConfig } from "./types";
@@ -66,7 +66,7 @@ const OBO_POOL_DEFAULTS = {
  */
 export class LakebasePlugin extends Plugin implements ToolProvider {
   /** Plugin manifest declaring metadata and resource requirements */
-  static manifest = manifest as PluginManifest<"lakebase">;
+  static manifest = defineManifest<"lakebase">(manifest);
 
   declare protected config: ILakebaseConfig;
   private pool: RoutingPool | null = null;
diff --git a/packages/appkit/src/plugins/server/index.ts b/packages/appkit/src/plugins/server/index.ts
index b882f6294..bcdea787a 100644
--- a/packages/appkit/src/plugins/server/index.ts
+++ b/packages/appkit/src/plugins/server/index.ts
@@ -12,7 +12,7 @@ import { AppKitError, ServerError } from "../../errors";
 import { TelemetryReporter } from "../../internal-telemetry";
 import { createLogger } from "../../logging/logger";
 import { Plugin, toPlugin } from "../../plugin";
-import type { PluginManifest } from "../../registry";
+import { defineManifest } from "../../registry";
 import { instrumentations } from "../../telemetry";
 import { sanitizeClientConfig } from "./client-config-sanitizer";
 import manifest from "./manifest.json";
@@ -66,7 +66,7 @@ export class ServerPlugin extends Plugin {
   private static readonly SERVER_CLOSE_TIMEOUT_MS = 2_000;
 
   /** Plugin manifest declaring metadata and resource requirements */
-  static manifest = manifest as PluginManifest<"server">;
+  static manifest = defineManifest<"server">(manifest);
   private serverApplication: express.Application;
   private server: HTTPServer | null;
   private viteDevServer?: ViteDevServer;
diff --git a/packages/appkit/src/plugins/serving/serving.ts b/packages/appkit/src/plugins/serving/serving.ts
index 8acfd4393..24097dc0a 100644
--- a/packages/appkit/src/plugins/serving/serving.ts
+++ b/packages/appkit/src/plugins/serving/serving.ts
@@ -9,8 +9,8 @@ import * as servingConnector from "../../connectors/serving/client";
 import { getWorkspaceClient } from "../../context";
 import { createLogger } from "../../logging";
 import { type ExecutionResult, Plugin, toPlugin } from "../../plugin";
-import type { PluginManifest, ResourceRequirement } from "../../registry";
-import { ResourceType } from "../../registry";
+import type { ResourceRequirement } from "../../registry";
+import { defineManifest, ResourceType } from "../../registry";
 import { servingInvokeDefaults } from "./defaults";
 import manifest from "./manifest.json";
 import { filterRequestBody, loadEndpointSchemas } from "./schema-filter";
@@ -42,7 +42,7 @@ interface ResolvedEndpoint {
 }
 
 export class ServingPlugin extends Plugin {
-  static manifest = manifest as PluginManifest<"serving">;
+  static manifest = defineManifest<"serving">(manifest);
 
   protected static description =
     "Authenticated proxy to Databricks Model Serving endpoints";
diff --git a/packages/appkit/src/registry/index.ts b/packages/appkit/src/registry/index.ts
index 08b1cc5fc..ceff9adfd 100644
--- a/packages/appkit/src/registry/index.ts
+++ b/packages/appkit/src/registry/index.ts
@@ -12,7 +12,11 @@
  * - (Future) Config generators for app.yaml, databricks.yml, .env.example
  */
 
-export { getPluginManifest, getResourceRequirements } from "./manifest-loader";
+export {
+  defineManifest,
+  getPluginManifest,
+  getResourceRequirements,
+} from "./manifest-loader";
 export { ResourceRegistry } from "./resource-registry";
 export * from "./types";
 
diff --git a/packages/appkit/src/registry/manifest-loader.ts b/packages/appkit/src/registry/manifest-loader.ts
index 255dddd70..470de802c 100644
--- a/packages/appkit/src/registry/manifest-loader.ts
+++ b/packages/appkit/src/registry/manifest-loader.ts
@@ -1,5 +1,4 @@
-import type { PluginConstructor } from "shared";
-
+import { type PluginConstructor, pluginManifestSchema } from "shared";
 import { ConfigurationError } from "../errors";
 import { createLogger } from "../logging/logger";
 import type {
@@ -11,6 +10,32 @@ import { PERMISSIONS_BY_TYPE, ResourceType } from "./types";
 
 const logger = createLogger("manifest-loader");
 
+/**
+ * Validates a raw manifest (typically a `manifest.json` import) against the
+ * canonical Zod schema and returns it as a strict {@link PluginManifest}.
+ *
+ * Plugins declare `static manifest = defineManifest<"my-plugin">(manifestJson)`
+ * instead of casting. A plain `as PluginManifest` can't work: a JSON import
+ * widens every field to `string`, and `PluginManifest.resources[].type` is the
+ * nominal `ResourceType` enum, so the structural JSON shape never assigns. The
+ * single internal assertion here bridges that gap in one audited place — after
+ * `parse()` has confirmed the values are real `ResourceType`/permission strings
+ * — rather than every plugin repeating `as unknown as PluginManifest`.
+ *
+ * Pass the plugin name as `TName` so the literal is preserved: `toPlugin`
+ * derives the typed plugin key from `manifest.name`, and a widened `string`
+ * there would collapse the typed plugin registry.
+ *
+ * @throws {ZodError} If the manifest doesn't match the schema.
+ */
+export function defineManifest<TName extends string = string>(
+  manifest: unknown,
+): PluginManifest<TName> {
+  return pluginManifestSchema.parse(
+    manifest,
+  ) as unknown as PluginManifest<TName>;
+}
+
 /** Loose resource from shared/manifest (string type and permission). */
 interface LooseResource {
   type: string;
diff --git a/packages/appkit/src/registry/tests/manifest-loader.test.ts b/packages/appkit/src/registry/tests/manifest-loader.test.ts
index 145ecd36d..732ed7b60 100644
--- a/packages/appkit/src/registry/tests/manifest-loader.test.ts
+++ b/packages/appkit/src/registry/tests/manifest-loader.test.ts
@@ -3,6 +3,7 @@ import { describe, expect, it } from "vitest";
 
 import { ConfigurationError } from "../../errors";
 import {
+  defineManifest,
   getPluginManifest,
   getResourceRequirements,
   isValidManifest,
@@ -555,4 +556,62 @@ describe("Manifest Loader", () => {
       expect(isValidManifest(valid)).toBe(true);
     });
   });
+
+  describe("defineManifest", () => {
+    const validManifest = {
+      name: "test-plugin",
+      displayName: "Test Plugin",
+      description: "A test plugin",
+      resources: {
+        required: [
+          {
+            type: "sql_warehouse",
+            alias: "warehouse",
+            resourceKey: "sql-warehouse",
+            description: "Test warehouse",
+            permission: "CAN_USE",
+            fields: { id: { env: "TEST_WAREHOUSE_ID" } },
+          },
+        ],
+        optional: [],
+      },
+    };
+
+    it("returns a schema-valid manifest unchanged", () => {
+      const result = defineManifest<"test-plugin">(validManifest);
+      expect(result.name).toBe("test-plugin");
+      expect(result.resources.required[0].type).toBe("sql_warehouse");
+    });
+
+    it("throws when a resource has an unknown type", () => {
+      const bad = {
+        ...validManifest,
+        resources: {
+          required: [
+            { ...validManifest.resources.required[0], type: "not_a_type" },
+          ],
+          optional: [],
+        },
+      };
+      expect(() => defineManifest(bad)).toThrow();
+    });
+
+    it("throws when a permission is invalid for the resource type", () => {
+      const bad = {
+        ...validManifest,
+        resources: {
+          required: [
+            { ...validManifest.resources.required[0], permission: "CAN_QUERY" },
+          ],
+          optional: [],
+        },
+      };
+      expect(() => defineManifest(bad)).toThrow();
+    });
+
+    it("throws when a required top-level field is missing", () => {
+      const { name: _omit, ...noName } = validManifest;
+      expect(() => defineManifest(noName)).toThrow();
+    });
+  });
 });
diff --git a/packages/shared/src/index.ts b/packages/shared/src/index.ts
index df3cbdd81..c8e7e8fa5 100644
--- a/packages/shared/src/index.ts
+++ b/packages/shared/src/index.ts
@@ -5,6 +5,7 @@ export * from "./genie";
 export * from "./metric-filter";
 export * from "./metric-metadata";
 export * from "./plugin";
+export { pluginManifestSchema } from "./schemas/manifest";
 export * from "./sql";
 export * from "./sse/analytics";
 export * from "./tunnel";