feat(core): support pinned Code Mode tools (#39550)

packages/schema/src/tool.ts

@@ -19,12 +19,23 @@ export interface Context {
   readonly progress: (update: Metadata) => Effect.Effect<void>
 }
 
-export interface Options {
+interface BaseOptions {
   readonly namespace?: string
-  readonly codemode?: boolean
   readonly permission?: string
 }
 
+export type Options = BaseOptions &
+  (
+    | {
+        readonly codemode?: true
+        readonly pinned?: boolean
+      }
+    | {
+        readonly codemode: boolean
+        readonly pinned?: never
+      }
+  )
+
 export type ValueSchema<A = unknown> =
   | Schema.Codec<A, any>
   | (StandardSchemaV1<any, A> & StandardJSONSchemaV1<any, A>)