diff --git a/Sources/SwiftLanguageService/CodeActions/AddMethodImplementation.swift b/Sources/SwiftLanguageService/CodeActions/AddMethodImplementation.swift
new file mode 100644
index 000000000..3e7f400a1
--- /dev/null
+++ b/Sources/SwiftLanguageService/CodeActions/AddMethodImplementation.swift
@@ -0,0 +1,298 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2025 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+import Foundation
+import LanguageServerProtocol
+@_spi(SourceKitLSP) import SKLogging
+import SourceKitLSP
+import SwiftParser
+import SwiftSyntax
+
+/// Provides code actions to add method implementations for incomplete implementations.
+public struct AddMethodImplementation {
+  
+  /// Creates code actions to add missing method implementations.
+  /// - Parameters:
+  ///   - diagnostics: The diagnostics that triggered this code action request
+  ///   - snapshot: The document snapshot
+  ///   - workspace: The workspace containing the document
+  /// - Returns: Array of code actions to add method implementations
+  static func codeActions(
+    diagnostics: [Diagnostic],
+    snapshot: DocumentSnapshot,
+    workspace: Workspace
+  ) -> [CodeAction] {
+    // Filter for incomplete implementation diagnostics
+    let incompleteDiagnostics = diagnostics.filter { diagnostic in
+      let message = diagnostic.message
+      return message.localizedCaseInsensitiveContains("incomplete implementation") ||
+      message.localizedCaseInsensitiveContains("does not conform to protocol") ||
+      message.localizedCaseInsensitiveContains("does not conform to") ||
+      message.localizedCaseInsensitiveContains("missing implementation")
+    }
+    
+    guard !incompleteDiagnostics.isEmpty else {
+      return []
+    }
+    
+    return generateAddMethodActions(
+      snapshot: snapshot,
+      workspace: workspace
+    )
+  }
+  
+  private static func generateAddMethodActions(
+    snapshot: DocumentSnapshot,
+    workspace: Workspace
+  ) -> [CodeAction] {
+    let text = snapshot.text
+    guard !text.isEmpty else {
+      return []
+    }
+    
+    // Detect file language
+    let fileExtension = URL(fileURLWithPath: snapshot.uri.pseudoPath).pathExtension
+    let isObjectiveC = fileExtension == "m" || fileExtension == "mm" || fileExtension == "h"
+    
+    if isObjectiveC {
+      return generateObjectiveCMethodActions(snapshot: snapshot, workspace: workspace)
+    } else {
+      // Swift implementation
+      return generateSwiftMethodActions(snapshot: snapshot, workspace: workspace)
+    }
+  }
+  
+  private static func generateObjectiveCMethodActions(
+    snapshot: DocumentSnapshot,
+    workspace: Workspace
+  ) -> [CodeAction] {
+    let text = snapshot.text
+    
+    // For Objective-C, look for incomplete implementation patterns
+    let missingMethods = findObjectiveCMissingMethods(in: text)
+    guard !missingMethods.isEmpty else {
+      return []
+    }
+    
+    return missingMethods.map { method in
+      let insertPosition = findObjectiveCInsertionPosition(in: text)
+      let edit = TextEdit(
+        range: insertPosition..<insertPosition,
+        newText: generateObjectiveCMethodImplementation(method: method)
+      )
+      
+      return CodeAction(
+        title: "Add implementation for '\(method.selector)'",
+        kind: .quickFix,
+        edit: WorkspaceEdit(changes: [snapshot.uri: [edit]])
+      )
+    }
+  }
+  
+  private static func generateSwiftMethodActions(
+    snapshot: DocumentSnapshot,
+    workspace: Workspace
+  ) -> [CodeAction] {
+    let text = snapshot.text
+    
+    // Parse the syntax tree to find incomplete implementations
+    let parseResult = Parser.parse(source: text)
+    let syntaxTree = parseResult
+    guard !syntaxTree.description.isEmpty else {
+      return []
+    }
+    
+    let missingMethods = findSwiftMissingMethods(in: syntaxTree, sourceText: text)
+    guard !missingMethods.isEmpty else {
+      return []
+    }
+    
+    // Find a good insertion point (end of class/struct)
+    guard let insertPosition = findSwiftInsertionPosition(in: syntaxTree, sourceText: text) else {
+      return []
+    }
+    
+    return missingMethods.map { method in
+      let edit = TextEdit(
+        range: insertPosition..<insertPosition,
+        newText: generateSwiftMethodImplementation(method: method)
+      )
+      
+      return CodeAction(
+        title: "Add implementation for '\(method.name)'",
+        kind: .quickFix,
+        edit: WorkspaceEdit(changes: [snapshot.uri: [edit]])
+      )
+    }
+  }
+  
+  private struct MissingMethod {
+    let name: String
+    let returnType: String
+    let parameters: [(name: String, type: String)]
+    let isStatic: Bool
+    let accessLevel: String
+  }
+  
+  private struct ObjectiveCMissingMethod {
+    let selector: String
+    let returnType: String
+    let parameters: [(name: String, type: String)]
+    let isClassMethod: Bool
+    let className: String
+  }
+  
+  private static func findSwiftMissingMethods(
+    in syntaxTree: SourceFileSyntax,
+    sourceText: String
+  ) -> [MissingMethod] {
+    let missingMethods: [MissingMethod] = []
+    
+    // Visit the syntax tree to find protocol conformance issues
+    class IncompleteImplementationVisitor: SyntaxVisitor {
+      let sourceText: String
+      var missingMethods: [MissingMethod] = []
+      
+      init(sourceText: String) {
+        self.sourceText = sourceText
+        super.init(viewMode: .sourceAccurate)
+      }
+      
+      override func visit(_ node: ClassDeclSyntax) -> SyntaxVisitorContinueKind {
+        checkForMissingImplementations(in: node, type: "class")
+        return .visitChildren
+      }
+      
+      override func visit(_ node: StructDeclSyntax) -> SyntaxVisitorContinueKind {
+        checkForMissingImplementations(in: node, type: "struct")
+        return .visitChildren
+      }
+      
+      private func checkForMissingImplementations<T: DeclSyntaxProtocol>(in node: T, type: String) {
+        // Look for diagnostics or comments indicating incomplete implementation
+        // This is a simplified approach - in a real implementation we'd want to
+        // use the compiler's diagnostic information more directly
+        // TODO: This is a placeholder implementation
+      }
+    }
+    
+    let visitor = IncompleteImplementationVisitor(sourceText: sourceText)
+    visitor.walk(syntaxTree)
+    
+    // For now, return empty array since we need more sophisticated analysis
+    // This would be enhanced with proper diagnostic correlation
+    return missingMethods
+  }
+  
+  private static func findObjectiveCMissingMethods(in text: String) -> [ObjectiveCMissingMethod] {
+    var missingMethods: [ObjectiveCMissingMethod] = []
+    
+    // Simple pattern matching for incomplete implementation warnings
+    // In a real implementation, this would be more sophisticated
+    let patterns = [
+      // Match patterns like "Method 'methodName:' in class 'ClassName' not found"
+      "Method '([^']+)' in class '([^']+)' not found",
+      // Match patterns like "Instance method 'methodName:' not implemented"
+      "Instance method '([^']+)' not implemented",
+      // Match patterns like "Class method 'methodName:' not implemented"
+      "Class method '([^']+)' not implemented"
+    ]
+    
+    for pattern in patterns {
+      guard let regex = try? NSRegularExpression(pattern: pattern) else {
+        continue
+      }
+      
+      let matches = regex.matches(in: text, options: [], range: NSRange(location: 0, length: text.utf16.count))
+      
+      for match in matches {
+        if match.numberOfRanges >= 3 {
+          let methodName = (text as NSString).substring(with: match.range(at: 1))
+          let className = (text as NSString).substring(with: match.range(at: 2))
+          
+          // Create a basic missing method structure
+          let missingMethod = ObjectiveCMissingMethod(
+            selector: methodName,
+            returnType: "void",
+            parameters: [],
+            isClassMethod: methodName.hasPrefix("+"),
+            className: className
+          )
+          missingMethods.append(missingMethod)
+        }
+      }
+    }
+    
+    return missingMethods
+  }
+  
+  private static func findSwiftInsertionPosition(
+    in syntaxTree: SourceFileSyntax,
+    sourceText: String
+  ) -> Position? {
+    // Find the last token in the main type declaration
+    if let lastToken = syntaxTree.lastToken(viewMode: .sourceAccurate) {
+      _ = lastToken.positionAfterSkippingLeadingTrivia
+      // Return a position at the end of the file
+      return Position(line: 999999, utf16index: 0)
+    }
+    
+    return Position(line: 0, utf16index: 0)
+  }
+  
+  private static func findObjectiveCInsertionPosition(in text: String) -> Position {
+    // Find the end of the last @implementation block or return beginning of file
+    if let range = text.range(of: "@end", options: .backwards) {
+      let lineStart = range.lowerBound
+      let lineNumber = text[..<lineStart].components(separatedBy: .newlines).count - 1
+      return Position(line: lineNumber, utf16index: 0)
+    }
+    
+    return Position(line: 0, utf16index: 0)
+  }
+  
+  private static func generateSwiftMethodImplementation(method: MissingMethod) -> String {
+    let accessPrefix = method.accessLevel.isEmpty ? "" : "\(method.accessLevel) "
+    let staticPrefix = method.isStatic ? "static " : ""
+    let parameters = method.parameters.map { "\($0.name): \($0.type)" }.joined(separator: ", ")
+    
+    return """
+
+    \(accessPrefix)\(staticPrefix)func \(method.name)(\(parameters)) -> \(method.returnType) {
+        // TODO: implement
+        fatalError("Not implemented")
+    }
+
+    """
+  }
+  
+  private static func generateObjectiveCMethodImplementation(method: ObjectiveCMissingMethod) -> String {
+    let methodPrefix = method.isClassMethod ? "+" : "-"
+    let parameters = method.parameters.map { "\($0.name):(\($0.type))\($0.name)" }.joined(separator: " ")
+    
+    return """
+
+    \(methodPrefix) (\(method.returnType))\(parameters) {
+        // TODO: implement
+        NSAssert(NO, @"Method not yet implemented");
+    }
+
+    """
+  }
+}
+
+// Helper extension to check if a string contains a substring (case-insensitive)
+extension String {
+  func localizedContains(_ searchString: String) -> Bool {
+    return localizedCaseInsensitiveContains(searchString)
+  }
+}
diff --git a/Sources/SwiftLanguageService/SwiftCommand.swift b/Sources/SwiftLanguageService/SwiftCommand.swift
index c6a51197a..a602001f0 100644
--- a/Sources/SwiftLanguageService/SwiftCommand.swift
+++ b/Sources/SwiftLanguageService/SwiftCommand.swift
@@ -53,6 +53,6 @@ extension SwiftLanguageService {
       ExpandMacroCommand.self,
     ].map { (command: any SwiftCommand.Type) in
       command.identifier
-    }
+    } + ["objective-c.add.method.implementation"]
   }
 }
diff --git a/Sources/SwiftLanguageService/SwiftLanguageService.swift b/Sources/SwiftLanguageService/SwiftLanguageService.swift
index 639a5a64a..570f2fd3c 100644
--- a/Sources/SwiftLanguageService/SwiftLanguageService.swift
+++ b/Sources/SwiftLanguageService/SwiftLanguageService.swift
@@ -898,6 +898,7 @@ extension SwiftLanguageService {
       (retrieveSyntaxCodeActions, nil),
       (retrieveRefactorCodeActions, .refactor),
       (retrieveQuickFixCodeActions, .quickFix),
+      (retrieveAddMethodImplementationCodeActions, .quickFix),
       (retrieveRemoveUnusedImportsCodeAction, .sourceOrganizeImports),
     ]
     let wantedActionKinds = req.context.only
@@ -948,6 +949,27 @@ extension SwiftLanguageService {
     }.flatMap { $0 }
   }
 
+  func retrieveAddMethodImplementationCodeActions(_ request: CodeActionRequest) async throws -> [CodeAction] {
+    guard
+      let sourceKitLSPServer,
+      let workspace = await sourceKitLSPServer.workspaceForDocument(
+        uri: request.textDocument.uri
+      )
+    else {
+      return []
+    }
+
+    let snapshot = try documentManager.latestSnapshot(
+      request.textDocument.uri
+    )
+
+    return AddMethodImplementation.codeActions(
+      diagnostics: request.context.diagnostics,
+      snapshot: snapshot,
+      workspace: workspace
+    )
+  }
+
   func retrieveRefactorCodeActions(_ params: CodeActionRequest) async throws -> [CodeAction] {
     let additionalCursorInfoParameters: ((SKDRequestDictionary) -> Void) = { skreq in
       skreq.set(self.keys.retrieveRefactorActions, to: 1)