feat: implement MCP logging/setLevel method handler

- Add logging/setLevel request handler to fix VSCode MCP protocol error
- Enhance logger with client-controlled log level filtering
- Support MCP log levels: emergency, alert, critical, error, warning, notice, info, debug
- Maintain test suppression logic for clean test output and doctor-cli
- Export setLogLevel() and getLogLevel() functions for MCP integration
- Return empty result as per MCP specification requirements

Fixes MCP -32601 "Method not found" error when VSCode tries to set logging levels.

Author: cameroncooke

README.md

@@ -29,6 +29,7 @@ A Model Context Protocol (MCP) server that provides Xcode-related tools for inte
 - [Dynamic Tools](#dynamic-tools)
   - [What is Dynamic Tools?](#what-is-dynamic-tools)
   - [How to Enable Dynamic Tools](#how-to-enable-dynamic-tools)
+  - [Selective Workflow Loading (Static Mode)](#selective-workflow-loading-static-mode)
   - [Usage Example](#usage-example)
   - [Client Compatibility](#client-compatibility)
 - [Code Signing for Device Deployment](#code-signing-for-device-deployment)
@@ -79,7 +80,7 @@ The XcodeBuildMCP server provides the following tool capabilities:
 - **Clean Artifacts**: Remove build artifacts and derived data for fresh builds
 
 ### Simulator management
-- **Simulator Control**: List, boot, and open simulators 
+- **Simulator Control**: List, boot, and open simulators
 - **App Lifecycle**: Complete app management - install, launch, and stop apps on simulators
 - **Log Capture**: Capture run-time logs from a simulator
 - **UI Automation**: Interact with simulator UI elements
@@ -121,7 +122,7 @@ For clients that support MCP resources XcodeBuildMCP provides efficient URI-base
 
 For a quick install, you can use the following links:
 
-- [![Install MCP Server](https://cursor.com/deeplink/mcp-install-dark.svg)](https://cursor.com/install-mcp?name=XcodeBuildMCP&config=eyJjb21tYW5kIjoibnB4IC15IHhjb2RlYnVpbGRtY3BAbGF0ZXN0In0%3D)
+- [![Install MCP Server](https://cursor.com/deeplink/mcp-install-dark.svg)](https://cursor.com/en/install-mcp?name=XcodeBuildMCP&config=eyJ0eXBlIjoic3RkaW8iLCJjb21tYW5kIjoibnB4IC15IHhjb2RlYnVpbGRtY3BAbGF0ZXN0IiwiZW52Ijp7IklOQ1JFTUVOVEFMX0JVSUxEU19FTkFCTEVEIjoiZmFsc2UiLCJYQ09ERUJVSUxETUNQX1NFTlRSWV9ESVNBQkxFRCI6ImZhbHNlIn19)
 - [<img src="https://img.shields.io/badge/VS_Code-VS_Code?style=flat-square&label=Install%20Server&color=0098FF" alt="Install in VS Code">](https://insiders.vscode.dev/redirect/mcp/install?name=XcodeBuildMCP&config=%7B%22command%22%3A%22npx%22%2C%22args%22%3A%5B%22-y%22%2C%22xcodebuildmcp%40latest%22%5D%7D)
 - [<img alt="Install in VS Code Insiders" src="https://img.shields.io/badge/VS_Code_Insiders-VS_Code_Insiders?style=flat-square&label=Install%20Server&color=24bfa5">](https://insiders.vscode.dev/redirect/mcp/install?name=XcodeBuildMCP&config=%7B%22command%22%3A%22npx%22%2C%22args%22%3A%5B%22-y%22%2C%22xcodebuildmcp%40latest%22%5D%7D&quality=insiders)
 
@@ -177,7 +178,7 @@ Then configure your MCP client to use mise to install XcodeBuildMCP:
 > When using mise avoid using the @latest tag as mise will cache the package and may not update to the latest version automatically, instead prefer an explicit version number.
 
 > [!IMPORTANT]
-> Please note that XcodeBuildMCP will request xcodebuild to skip macro validation. This is to avoid errors when building projects that use Swift Macros. 
+> Please note that XcodeBuildMCP will request xcodebuild to skip macro validation. This is to avoid errors when building projects that use Swift Macros.
 
 #### Installing via Smithery
 
@@ -194,7 +195,7 @@ XcodeBuildMCP supports both MCP tools, resources and sampling. At time of writin
 | Editor | Tools | Resources | Samplng |
 |--------|-------|-----------|---------|
 | **VS Code** | ✅ | ✅ | ✅ |
-| **Cursor** | ✅ | ❌ | ❌ | 
+| **Cursor** | ✅ | ❌ | ❌ |
 | **Windsurf** | ✅ | ❌ | ❌ |
 | **Claude Code** | ✅ | ✅ | ❌ |
 | **Claude Desktop** | ✅ | ✅ | ❌ |
@@ -217,7 +218,7 @@ Example MCP client configuration:
       ],
       "env": {
         "INCREMENTAL_BUILDS_ENABLED": "true"
-      }        
+      }
     }
   }
 }
@@ -255,7 +256,7 @@ Example MCP client configuration:
       ],
       "env": {
         "XCODEBUILDMCP_DYNAMIC_TOOLS": "true"
-      }        
+      }
     }
   }
 }
@@ -276,7 +277,7 @@ For clients that don't support MCP Sampling but still want to reduce context win
       ],
       "env": {
         "XCODEBUILDMCP_ENABLED_WORKFLOWS": "simulator,device,project-discovery"
-      }        
+      }
     }
   }
 }
@@ -362,7 +363,7 @@ This project uses [Sentry](https://sentry.io/) for error monitoring and diagnost
 - Error logs may include details such as error messages, stack traces, and (in some cases) file paths or project names. You can review the sources in this repository to see exactly what is logged.
 
 ### Opting Out of Sentry
-- If you do not wish to send error logs to Sentry, you can opt out by setting the environment variable `SENTRY_DISABLED=true`.
+- If you do not wish to send error logs to Sentry, you can opt out by setting the environment variable `XCODEBUILDMCP_SENTRY_DISABLED=true`.
 
 Example MCP client configuration:
 ```json
@@ -375,8 +376,8 @@ Example MCP client configuration:
         "xcodebuildmcp@latest"
       ],
       "env": {
-        "SENTRY_DISABLED": "true"
-      }        
+        "XCODEBUILDMCP_SENTRY_DISABLED": "true"
+      }
     }
   }
 }

src/index.ts

@@ -20,8 +20,11 @@ import './utils/sentry.ts';
 import { createServer, startServer } from './server/server.ts';
 import { McpServer } from '@camsoft/mcp-sdk/server/mcp.js';
 
+// Import MCP types for logging
+import { SetLevelRequestSchema } from '@camsoft/mcp-sdk/types.js';
+
 // Import utilities
-import { log } from './utils/logger.ts';
+import { log, setLogLevel, type LogLevel } from './utils/logger.ts';
 
 // Import version
 import { version } from './version.ts';
@@ -64,6 +67,14 @@ async function main(): Promise<void> {
     // Create the server
     const server = createServer();
 
+    // Register logging/setLevel handler
+    server.server.setRequestHandler(SetLevelRequestSchema, async (request) => {
+      const { level } = request.params;
+      setLogLevel(level as LogLevel);
+      log('info', `Client requested log level: ${level}`);
+      return {}; // Empty result as per MCP spec
+    });
+
     // Make server available globally for dynamic tools
     (globalThis as { mcpServer?: McpServer }).mcpServer = server;
 

src/utils/logger.ts

@@ -23,6 +23,23 @@ import { createRequire } from 'node:module';
 const SENTRY_ENABLED =
   process.env.SENTRY_DISABLED !== 'true' && process.env.XCODEBUILDMCP_SENTRY_DISABLED !== 'true';
 
+// Log levels in order of severity (lower number = more severe)
+const LOG_LEVELS = {
+  emergency: 0,
+  alert: 1,
+  critical: 2,
+  error: 3,
+  warning: 4,
+  notice: 5,
+  info: 6,
+  debug: 7,
+} as const;
+
+export type LogLevel = keyof typeof LOG_LEVELS;
+
+// Client-requested log level (null means no filtering)
+let clientLogLevel: LogLevel | null = null;
+
 function isTestEnv(): boolean {
   return (
     process.env.VITEST === 'true' ||
@@ -66,18 +83,57 @@ if (!SENTRY_ENABLED) {
   }
 }
 
+/**
+ * Set the minimum log level for client-requested filtering
+ * @param level The minimum log level to output
+ */
+export function setLogLevel(level: LogLevel): void {
+  clientLogLevel = level;
+  log('debug', `Log level set to: ${level}`);
+}
+
+/**
+ * Get the current client-requested log level
+ * @returns The current log level or null if no filtering is active
+ */
+export function getLogLevel(): LogLevel | null {
+  return clientLogLevel;
+}
+
+/**
+ * Check if a log level should be output based on client settings
+ * @param level The log level to check
+ * @returns true if the message should be logged
+ */
+function shouldLog(level: string): boolean {
+  // Suppress logging during tests to keep test output clean
+  if (isTestEnv()) {
+    return false;
+  }
+
+  // If no client level set, log everything
+  if (clientLogLevel === null) {
+    return true;
+  }
+
+  // Check if the level is valid
+  const levelKey = level.toLowerCase() as LogLevel;
+  if (!(levelKey in LOG_LEVELS)) {
+    return true; // Log unknown levels
+  }
+
+  // Only log if the message level is at or above the client's requested level
+  return LOG_LEVELS[levelKey] <= LOG_LEVELS[clientLogLevel];
+}
+
 /**
  * Log a message with the specified level
- * @param level The log level (info, warning, error, debug)
+ * @param level The log level (emergency, alert, critical, error, warning, notice, info, debug)
  * @param message The message to log
  */
 export function log(level: string, message: string): void {
-  // Suppress logging during tests to keep test output clean
-  if (
-    process.env.VITEST === 'true' ||
-    process.env.NODE_ENV === 'test' ||
-    process.env.XCODEBUILDMCP_SILENCE_LOGS === 'true'
-  ) {
+  // Check if we should log this level
+  if (!shouldLog(level)) {
     return;
   }