feat(mcp): restore Exa websearch support (#549)

* feat(mcp): restore Exa MCP websearch support

- Add websearch.ts with Exa remote MCP configuration
- Update McpNameSchema to include websearch
- Wire websearch MCP into plugin initialization

🤖 GENERATED WITH ASSISTANCE OF [OhMyOpenCode](https://github.com/code-yeongyu/oh-my-opencode)

* test(mcp): update tests and docs for websearch MCP

- Update index.test.ts to verify 3 MCPs (websearch, context7, grep_app)
- Add Exa/websearch documentation to README.md MCPs section

🤖 GENERATED WITH ASSISTANCE OF [OhMyOpenCode](https://github.com/code-yeongyu/oh-my-opencode)

README.md

@@ -582,6 +582,7 @@ These tools enable agents to reference previous conversations and maintain conti
     - Use camelCase for function names
     ```
 - **Online**: Project rules aren't everything. Built-in MCPs for extended capabilities:
+  - **websearch**: Real-time web search powered by [Exa AI](https://exa.ai)
   - **context7**: Official documentation lookup
   - **grep_app**: Ultra-fast code search across public GitHub repos (great for finding implementation examples)
 
@@ -983,8 +984,9 @@ Available hooks: `todo-continuation-enforcer`, `context-window-monitor`, `sessio
 
 ### MCPs
 
-Context7 and grep.app MCP enabled by default.
+Exa, Context7 and grep.app MCP enabled by default.
 
+- **websearch**: Real-time web search powered by [Exa AI](https://exa.ai) - searches the web and returns relevant content
 - **context7**: Fetches up-to-date official documentation for libraries
 - **grep_app**: Ultra-fast code search across millions of public GitHub repositories via [grep.app](https://grep.app)
 
@@ -992,7 +994,7 @@ Don't want them? Disable via `disabled_mcps` in `~/.config/opencode/oh-my-openco
 
 ```json
 {
-  "disabled_mcps": ["context7", "grep_app"]
+  "disabled_mcps": ["websearch", "context7", "grep_app"]
 }
 ```
 

src/mcp/index.test.ts

@@ -10,9 +10,10 @@ describe("createBuiltinMcps", () => {
     const result = createBuiltinMcps(disabledMcps)
 
     //#then
+    expect(result).toHaveProperty("websearch")
     expect(result).toHaveProperty("context7")
     expect(result).toHaveProperty("grep_app")
-    expect(Object.keys(result)).toHaveLength(2)
+    expect(Object.keys(result)).toHaveLength(3)
   })
 
   test("should filter out disabled built-in MCPs", () => {
@@ -23,19 +24,21 @@ describe("createBuiltinMcps", () => {
     const result = createBuiltinMcps(disabledMcps)
 
     //#then
+    expect(result).toHaveProperty("websearch")
     expect(result).not.toHaveProperty("context7")
     expect(result).toHaveProperty("grep_app")
-    expect(Object.keys(result)).toHaveLength(1)
+    expect(Object.keys(result)).toHaveLength(2)
   })
 
-  test("should filter out both built-in MCPs when both disabled", () => {
+  test("should filter out all built-in MCPs when all disabled", () => {
     //#given
-    const disabledMcps = ["context7", "grep_app"]
+    const disabledMcps = ["websearch", "context7", "grep_app"]
 
     //#when
     const result = createBuiltinMcps(disabledMcps)
 
     //#then
+    expect(result).not.toHaveProperty("websearch")
     expect(result).not.toHaveProperty("context7")
     expect(result).not.toHaveProperty("grep_app")
     expect(Object.keys(result)).toHaveLength(0)
@@ -49,9 +52,10 @@ describe("createBuiltinMcps", () => {
     const result = createBuiltinMcps(disabledMcps)
 
     //#then
+    expect(result).toHaveProperty("websearch")
     expect(result).not.toHaveProperty("context7")
     expect(result).toHaveProperty("grep_app")
-    expect(Object.keys(result)).toHaveLength(1)
+    expect(Object.keys(result)).toHaveLength(2)
   })
 
   test("should handle empty disabled_mcps by default", () => {
@@ -60,9 +64,10 @@ describe("createBuiltinMcps", () => {
     const result = createBuiltinMcps()
 
     //#then
+    expect(result).toHaveProperty("websearch")
     expect(result).toHaveProperty("context7")
     expect(result).toHaveProperty("grep_app")
-    expect(Object.keys(result)).toHaveLength(2)
+    expect(Object.keys(result)).toHaveLength(3)
   })
 
   test("should only filter built-in MCPs, ignoring unknown names", () => {
@@ -73,8 +78,9 @@ describe("createBuiltinMcps", () => {
     const result = createBuiltinMcps(disabledMcps)
 
     //#then
+    expect(result).toHaveProperty("websearch")
     expect(result).toHaveProperty("context7")
     expect(result).toHaveProperty("grep_app")
-    expect(Object.keys(result)).toHaveLength(2)
+    expect(Object.keys(result)).toHaveLength(3)
   })
 })

src/mcp/index.ts

@@ -1,3 +1,4 @@
+import { websearch } from "./websearch"
 import { context7 } from "./context7"
 import { grep_app } from "./grep-app"
 import type { McpName } from "./types"
@@ -5,6 +6,7 @@ import type { McpName } from "./types"
 export { McpNameSchema, type McpName } from "./types"
 
 const allBuiltinMcps: Record<McpName, { type: "remote"; url: string; enabled: boolean }> = {
+  websearch,
   context7,
   grep_app,
 }

src/mcp/types.ts

@@ -1,6 +1,6 @@
 import { z } from "zod"
 
-export const McpNameSchema = z.enum(["context7", "grep_app"])
+export const McpNameSchema = z.enum(["websearch", "context7", "grep_app"])
 
 export type McpName = z.infer<typeof McpNameSchema>
 

src/mcp/websearch.ts

@@ -0,0 +1,5 @@
+export const websearch = {
+  type: "remote" as const,
+  url: "https://mcp.exa.ai/mcp?tools=web_search_exa",
+  enabled: true,
+}