diff --git a/packages/opencode/src/agent/agent.ts b/packages/opencode/src/agent/agent.ts
index d96e508c9d02..b9b56396fac2 100644
--- a/packages/opencode/src/agent/agent.ts
+++ b/packages/opencode/src/agent/agent.ts
@@ -1,5 +1,4 @@
 import { Config } from "@/config/config"
-import z from "zod"
 import { Provider } from "@/provider/provider"
 import { ModelID, ProviderID } from "../provider/schema"
 import { generateObject, streamObject, type ModelMessage } from "ai"
@@ -49,6 +48,12 @@ export const Info = Schema.Struct({
 }).annotate({ identifier: "Agent" })
 export type Info = DeepMutable<Schema.Schema.Type<typeof Info>>
 
+const GeneratedAgent = Schema.Struct({
+  identifier: Schema.String,
+  whenToUse: Schema.String,
+  systemPrompt: Schema.String,
+})
+
 export interface Interface {
   readonly get: (agent: string) => Effect.Effect<Info>
   readonly list: () => Effect.Effect<Info[]>
@@ -405,11 +410,10 @@ export const layer = Layer.effect(
             },
           ],
           model: language,
-          schema: z.object({
-            identifier: z.string(),
-            whenToUse: z.string(),
-            systemPrompt: z.string(),
-          }),
+          schema: Object.assign(
+            Schema.toStandardSchemaV1(GeneratedAgent),
+            Schema.toStandardJSONSchemaV1(GeneratedAgent),
+          ),
         } satisfies Parameters<typeof generateObject>[0]
 
         if (isOpenaiOauth) {