feat(core): add pinned Code Mode tools

packages/plugin/src/v2/effect/internal/tool.ts

@@ -129,6 +129,8 @@ export interface RegisterOptions {
   readonly namespace?: string
   /** Defaults to true. False exposes the tool directly to the provider. */
   readonly codemode?: boolean
+  /** Keeps the complete signature visible when the Code Mode catalog is compact. */
+  readonly pinned?: boolean
   /** Permission action used for whole-tool visibility filtering. */
   readonly permission?: string
 }
@@ -138,6 +140,7 @@ export interface Registration {
   readonly name: string
   readonly namespace?: string
   readonly permission: string
+  readonly pinned?: boolean
 }
 
 export const validateName = (name: string) =>
@@ -159,6 +162,7 @@ export const registrationEntries = (
       namespace: options?.namespace,
       tool,
       permission: options?.permission ?? key,
+      ...(options?.pinned === true ? { pinned: true } : {}),
     }
   })
 

packages/plugin/test/tool.test.ts

@@ -125,3 +125,16 @@ test("raw JSON schemas are render-only and omitted output means model-only", asy
   })
   expect(await Effect.runPromise(Tool.decodeInput(tool.input, { value: 1 }))).toEqual({ value: 1 })
 })
+
+test("registration metadata omits disabled pinning", () => {
+  const tool = Tool.make({
+    description: "Echo text",
+    input: Schema.Struct({ text: Schema.String }),
+    output: Schema.String,
+    execute: ({ text }) => Effect.succeed({ output: text }),
+  })
+  const registration = Tool.registrationEntries({ echo: tool })
+
+  expect(Tool.registrationEntries({ echo: tool }, { pinned: false })).toEqual(registration)
+  expect(Tool.registrationEntries({ echo: tool }, { pinned: true })).toEqual([{ ...registration[0], pinned: true }])
+})