diff --git a/.changeset/template-manifest-not-strict.md b/.changeset/template-manifest-not-strict.md
new file mode 100644
index 0000000..fa389a1
--- /dev/null
+++ b/.changeset/template-manifest-not-strict.md
@@ -0,0 +1,5 @@
+---
+"@generata/core": patch
+---
+
+fix: make TemplateManifest schema strict to reject unknown keys
diff --git a/packages/core/src/cli/manifest.test.ts b/packages/core/src/cli/manifest.test.ts
index aaf9b08..327c698 100644
--- a/packages/core/src/cli/manifest.test.ts
+++ b/packages/core/src/cli/manifest.test.ts
@@ -43,6 +43,13 @@ describe("parseManifest", () => {
   it("rejects bin entry missing name", () => {
     throws(() => parseManifest({ name: "x", description: "y", requiredBins: [{}] }));
   });
+
+  it("rejects unknown top-level keys", () => {
+    throws(
+      () => parseManifest({ name: "x", description: "y", requireBins: [] }),
+      /requireBins/,
+    );
+  });
 });
 
 describe("loadManifest", () => {
diff --git a/packages/core/src/cli/manifest.ts b/packages/core/src/cli/manifest.ts
index 348e219..4380ae0 100644
--- a/packages/core/src/cli/manifest.ts
+++ b/packages/core/src/cli/manifest.ts
@@ -15,15 +15,17 @@ const RequiredEnvEntry = z.object({
   optional: z.boolean().default(false),
 });
 
-export const TemplateManifest = z.object({
-  name: z.string(),
-  description: z.string(),
-  engineVersion: z.string().optional(),
-  requiredBins: z.array(RequiredBin).default([]),
-  requiredEnv: z.record(z.string(), RequiredEnvEntry).default({}),
-  installPaths: z.record(z.string(), z.string()).default({}),
-  postInstall: z.string().optional(),
-});
+export const TemplateManifest = z
+  .object({
+    name: z.string(),
+    description: z.string(),
+    engineVersion: z.string().optional(),
+    requiredBins: z.array(RequiredBin).default([]),
+    requiredEnv: z.record(z.string(), RequiredEnvEntry).default({}),
+    installPaths: z.record(z.string(), z.string()).default({}),
+    postInstall: z.string().optional(),
+  })
+  .strict();
 export type TemplateManifest = z.infer<typeof TemplateManifest>;
 
 export function parseManifest(input: unknown): TemplateManifest {