refactor: replace fetch_instructions tool with built-in skills

- Add built-in skills (create-mcp-server, create-mode) following slash commands pattern
- Update SkillsManager to merge built-in skills with user skills
- Remove FetchInstructionsTool and related infrastructure
- Remove enableMcpServerCreation setting and UI checkbox
- Remove auto-approval logic for fetchInstructions
- Update system prompt sections to remove fetch_instructions references

Built-in skills are now available through the skills system with
override precedence: project > global > built-in

Author: hannesrudolph

packages/types/src/global-settings.ts

@@ -174,7 +174,6 @@ export const globalSettingsSchema = z.object({
 	telemetrySetting: telemetrySettingsSchema.optional(),
 
 	mcpEnabled: z.boolean().optional(),
-	enableMcpServerCreation: z.boolean().optional(),
 
 	mode: z.string().optional(),
 	modeApiConfigs: z.record(z.string(), z.string()).optional(),

packages/types/src/tool.ts

@@ -32,7 +32,6 @@ export const toolNames = [
 	"attempt_completion",
 	"switch_mode",
 	"new_task",
-	"fetch_instructions",
 	"codebase_search",
 	"update_todo_list",
 	"run_slash_command",

packages/types/src/vscode-extension-host.ts

@@ -365,7 +365,6 @@ export type ExtensionState = Pick<
 	experiments: Experiments // Map of experiment IDs to their enabled state
 
 	mcpEnabled: boolean
-	enableMcpServerCreation: boolean
 
 	mode: string
 	customModes: ModeConfig[]
@@ -505,7 +504,6 @@ export interface WebviewMessage {
 		| "deleteMessageConfirm"
 		| "submitEditedMessage"
 		| "editMessageConfirm"
-		| "enableMcpServerCreation"
 		| "remoteControlEnabled"
 		| "taskSyncEnabled"
 		| "searchCommits"
@@ -786,7 +784,6 @@ export interface ClineSayTool {
 		| "newFileCreated"
 		| "codebaseSearch"
 		| "readFile"
-		| "fetchInstructions"
 		| "listFilesTopLevel"
 		| "listFilesRecursive"
 		| "searchFiles"

src/core/assistant-message/NativeToolCallParser.ts

@@ -449,14 +449,6 @@ export class NativeToolCallParser {
 				}
 				break
 
-			case "fetch_instructions":
-				if (partialArgs.task !== undefined) {
-					nativeArgs = {
-						task: partialArgs.task,
-					}
-				}
-				break
-
 			case "generate_image":
 				if (partialArgs.prompt !== undefined || partialArgs.path !== undefined) {
 					nativeArgs = {
@@ -736,14 +728,6 @@ export class NativeToolCallParser {
 					}
 					break
 
-				case "fetch_instructions":
-					if (args.task !== undefined) {
-						nativeArgs = {
-							task: args.task,
-						} as NativeArgsFor<TName>
-					}
-					break
-
 				case "generate_image":
 					if (args.prompt !== undefined && args.path !== undefined) {
 						nativeArgs = {

src/core/assistant-message/presentAssistantMessage.ts

@@ -15,7 +15,6 @@ import { experiments, EXPERIMENT_IDS } from "../../shared/experiments"
 import { AskIgnoredError } from "../task/AskIgnoredError"
 import { Task } from "../task/Task"
 
-import { fetchInstructionsTool } from "../tools/FetchInstructionsTool"
 import { listFilesTool } from "../tools/ListFilesTool"
 import { readFileTool } from "../tools/ReadFileTool"
 import { writeToFileTool } from "../tools/WriteToFileTool"
@@ -364,8 +363,6 @@ export async function presentAssistantMessage(cline: Task) {
 							return readFileTool.getReadFileToolDescription(block.name, block.nativeArgs)
 						}
 						return readFileTool.getReadFileToolDescription(block.name, block.params)
-					case "fetch_instructions":
-						return `[${block.name} for '${block.params.task}']`
 					case "write_to_file":
 						return `[${block.name} for '${block.params.path}']`
 					case "apply_diff":
@@ -809,13 +806,6 @@ export async function presentAssistantMessage(cline: Task) {
 						pushToolResult,
 					})
 					break
-				case "fetch_instructions":
-					await fetchInstructionsTool.handle(cline, block as ToolUse<"fetch_instructions">, {
-						askApproval,
-						handleError,
-						pushToolResult,
-					})
-					break
 				case "list_files":
 					await listFilesTool.handle(cline, block as ToolUse<"list_files">, {
 						askApproval,
@@ -1090,7 +1080,6 @@ function containsXmlToolMarkup(text: string): boolean {
 		"codebase_search",
 		"edit_file",
 		"execute_command",
-		"fetch_instructions",
 		"generate_image",
 		"list_files",
 		"new_task",

src/core/auto-approval/index.ts

@@ -151,16 +151,6 @@ export async function checkAutoApproval({
 			return { decision: "approve" }
 		}
 
-		if (tool?.tool === "fetchInstructions") {
-			if (tool.content === "create_mode") {
-				return state.alwaysAllowModeSwitch === true ? { decision: "approve" } : { decision: "ask" }
-			}
-
-			if (tool.content === "create_mcp_server") {
-				return state.alwaysAllowMcp === true ? { decision: "approve" } : { decision: "ask" }
-			}
-		}
-
 		if (tool?.tool === "switchMode") {
 			return state.alwaysAllowModeSwitch === true ? { decision: "approve" } : { decision: "ask" }
 		}

src/core/prompts/__tests__/__snapshots__/add-custom-instructions/mcp-server-creation-enabled.snap

@@ -212,7 +212,6 @@ describe("addCustomInstructions", () => {
 			undefined, // globalCustomInstructions
 			undefined, // diffEnabled
 			undefined, // experiments
-			true, // enableMcpServerCreation
 			undefined, // language
 			undefined, // rooIgnoreInstructions
 			undefined, // partialReadsEnabled
@@ -235,7 +234,6 @@ describe("addCustomInstructions", () => {
 			undefined, // globalCustomInstructions
 			undefined, // diffEnabled
 			undefined, // experiments
-			true, // enableMcpServerCreation
 			undefined, // language
 			undefined, // rooIgnoreInstructions
 			undefined, // partialReadsEnabled
@@ -244,7 +242,7 @@ describe("addCustomInstructions", () => {
 		expect(prompt).toMatchFileSnapshot("./__snapshots__/add-custom-instructions/ask-mode-prompt.snap")
 	})
 
-	it("should include MCP server creation info when enabled", async () => {
+	it("should include MCP server info when enabled", async () => {
 		const mockMcpHub = createMockMcpHub(true)
 
 		const prompt = await SYSTEM_PROMPT(
@@ -260,13 +258,14 @@ describe("addCustomInstructions", () => {
 			undefined, // globalCustomInstructions
 			undefined, // diffEnabled
 			undefined, // experiments
-			true, // enableMcpServerCreation
 			undefined, // language
 			undefined, // rooIgnoreInstructions
 			undefined, // partialReadsEnabled
 		)
 
-		expect(prompt).toContain("Creating an MCP Server")
+		// MCP server section should be present with connected servers info
+		expect(prompt).toContain("MCP SERVERS")
+		expect(prompt).toContain("Connected MCP Servers")
 		expect(prompt).toMatchFileSnapshot("./__snapshots__/add-custom-instructions/mcp-server-creation-enabled.snap")
 	})
 
@@ -286,7 +285,6 @@ describe("addCustomInstructions", () => {
 			undefined, // globalCustomInstructions
 			undefined, // diffEnabled
 			undefined, // experiments
-			false, // enableMcpServerCreation
 			undefined, // language
 			undefined, // rooIgnoreInstructions
 			undefined, // partialReadsEnabled
@@ -310,7 +308,6 @@ describe("addCustomInstructions", () => {
 			undefined, // globalCustomInstructions
 			undefined, // diffEnabled
 			undefined, // experiments
-			true, // enableMcpServerCreation
 			undefined, // language
 			undefined, // rooIgnoreInstructions
 			true, // partialReadsEnabled

src/core/prompts/__tests__/__snapshots__/system-prompt/with-mcp-hub-provided.snap

@@ -106,7 +106,6 @@ describe("File-Based Custom System Prompt", () => {
 				undefined, // globalCustomInstructions
 				undefined, // diffEnabled
 				undefined, // experiments
-				true, // enableMcpServerCreation
 				undefined, // language
 				undefined, // rooIgnoreInstructions
 				undefined, // partialReadsEnabled
@@ -144,7 +143,6 @@ describe("File-Based Custom System Prompt", () => {
 			undefined, // globalCustomInstructions
 			undefined, // diffEnabled
 			undefined, // experiments
-			true, // enableMcpServerCreation
 			undefined, // language
 			undefined, // rooIgnoreInstructions
 			undefined, // partialReadsEnabled
@@ -190,7 +188,6 @@ describe("File-Based Custom System Prompt", () => {
 			undefined, // globalCustomInstructions
 			undefined, // diffEnabled
 			undefined, // experiments
-			true, // enableMcpServerCreation
 			undefined, // language
 			undefined, // rooIgnoreInstructions
 			undefined, // partialReadsEnabled