fix(delegate-task): reject primary agents in task subagent resolution

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/tools/delegate-task/task-schema.test.ts

@@ -31,4 +31,20 @@ function createDelegateTask(...args: Parameters<typeof import("./tools").createD
 		expect(categorySchema.def.type).toBe("optional")
 		expect(categorySchema.def.innerType.def.type).toBe("string")
 	})
+
+	test("#given task description #when tool is created #then primary agents are not advertised for subagent_type", () => {
+		//#given
+		const toolDefinition = createDelegateTask({ manager: {} as never, client: {} as never, directory: "/tmp/test" })
+
+		//#when
+		const description = toolDefinition.description
+
+		//#then
+		expect(description).toContain("subagent_type: Use specific agent directly")
+		expect(description).not.toContain("sisyphus")
+		expect(description).not.toContain("hephaestus")
+		expect(description).not.toContain("prometheus")
+	})
 })
+
+export {}