feat(core): add grouped and deferred tool registration (#35232)

packages/core/test/mcp.test.ts

@@ -1,6 +1,7 @@
 import { describe, expect, test } from "bun:test"
 import { MCP } from "@opencode-ai/core/mcp/index"
 import { MCPClient } from "@opencode-ai/core/mcp/client"
+import { McpTool } from "@opencode-ai/core/tool/mcp"
 
 describe("MCP errors", () => {
   test("expose useful messages", () => {
@@ -12,3 +13,7 @@ describe("MCP errors", () => {
     expect(new MCPClient.ConnectError({ server: "demo", message: "offline" }).message).toBe("offline")
   })
 })
+
+test("MCP tool names match V1 sanitization", () => {
+  expect(McpTool.name("context 7", "resolve.library/id")).toBe("context_7_resolve_library_id")
+})

packages/core/test/plugin.test.ts

@@ -126,6 +126,38 @@ describe("PluginV2", () => {
     }),
   )
 
+  it.effect("groups tool names and defers registrations from direct exposure", () =>
+    Effect.gen(function* () {
+      const plugins = yield* PluginV2.Service
+      const registry = yield* ToolRegistry.Service
+      const tool = (description: string) =>
+        Tool.make({
+          description,
+          input: Schema.Struct({}),
+          output: Schema.Struct({ ok: Schema.Boolean }),
+          execute: () => Effect.succeed({ ok: true }),
+        })
+      const plugin = define({
+        id: "grouped-tools",
+        effect: (ctx) =>
+          Effect.gen(function* () {
+            yield* ctx.tool.register({ plain: tool("Plain") }).pipe(Effect.orDie)
+            yield* ctx.tool.register({ "look/up": tool("Lookup") }, { group: "context 7" }).pipe(Effect.orDie)
+            yield* ctx.tool
+              .register({ search: tool("Search") }, { group: "context 7", deferred: true })
+              .pipe(Effect.orDie)
+          }),
+      })
+
+      yield* plugins.add(PluginV2.ID.make(plugin.id), plugin.effect)
+
+      expect((yield* registry.materialize({ model: testModel })).definitions.map((tool) => tool.name)).toEqual([
+        "plain",
+        "context_7_look_up",
+      ])
+    }),
+  )
+
   it.effect("fires before/after tool hooks with mutable events around settlement", () =>
     Effect.gen(function* () {
       const plugins = yield* PluginV2.Service