Expand WordPress Intelligence support to other locales

Modules/Sources/WordPressShared/Intelligence/IntelligenceService.swift

@@ -45,7 +45,7 @@ public actor IntelligenceService {
         // - `useCase: .contentTagging` is not recommended for arbitraty hashtags
 
         let instructions = """
-        You are helping a WordPress user add tags to a post or a page.
+        \(makeLocaleInstructions())You are helping a WordPress user add tags to a post or a page.
 
         **Parameters**
         - POST_CONTENT: contents of the post (HTML or plain text)
@@ -54,9 +54,12 @@ public actor IntelligenceService {
 
         **Steps**
         - 1. Identify the specific formatting pattern used (e.g., lowercase with underscores, capitalized words with spaces, etc)
-        - 2. Generate a list of ten most relevant suggested tags based on POST_CONTENT and SITE_TAGS relevant to the content.
+        - 2. Identify the language used in SITE_TAGS and POST_CONTENT
+        - 3. Generate a list of ten most relevant suggested tags based on POST_CONTENT and SITE_TAGS relevant to the content.
 
         **Requirements**
+        - You MUST generate tags in the same language as SITE_TAGS and POST_CONTENT
+        - Tags MUST match the formatting pattern and language of existing tags
         - Do not include any tags from EXISTING_POST_TAGS
         - If there are no relevant suggestions, returns an empty list
         - Do not produce any output other than the final list of tag
@@ -101,9 +104,10 @@ public actor IntelligenceService {
         let content = extractRelevantText(from: content, ratio: 0.8)
 
         let instructions = """
-        You are helping a WordPress user understand the content of a post.
+        \(makeLocaleInstructions())You are helping a WordPress user understand the content of a post.
         Generate a concise summary that captures the main points and key information.
         The summary should be clear, informative, and written in a neutral tone.
+        You MUST generate the summary in the same language as the post content.
 
         Do not include anything other than the summary in the response.
         """
@@ -124,10 +128,11 @@ public actor IntelligenceService {
 
     public func summarizeSupportTicket(content: String) async throws -> String {
         let instructions = """
-        You are helping a user by summarizing their support request down to a single sentence
+        \(makeLocaleInstructions())You are helping a user by summarizing their support request down to a single sentence
         with fewer than 10 words.
 
         The summary should be clear, informative, and written in a neutral tone.
+        You MUST generate the summary in the same language as the support request.
 
         Do not include anything other than the summary in the response.
         """
@@ -155,6 +160,19 @@ public actor IntelligenceService {
         let postSizeLimit = Double(IntelligenceService.contextSizeLimit) * ratio
         return String((extract ?? post).prefix(Int(postSizeLimit)))
     }
+
+    /// Generates locale-specific instructions for the language model.
+    ///
+    /// Following Apple's recommended approach for multilingual support:
+    /// https://developer.apple.com/documentation/foundationmodels/support-languages-and-locales-with-foundation-models
+    private nonisolated func makeLocaleInstructions(for locale: Locale = .current) -> String {
+        // Skip the locale phrase for U.S. English (Apple's recommendation)
+        if Locale.Language(identifier: "en_US").isEquivalent(to: locale.language) {
+            return ""
+        }
+        // Use the exact phrase format recommended by Apple to reduce hallucinations
+        return "The person's locale is \(locale.identifier).\n"
+    }
 }
 
 private extension Array where Element: Hashable {

RELEASE-NOTES.txt

@@ -1,6 +1,6 @@
 26.6
 -----
-
+* [**] [Intelligence] Expand AI-based features to more locales [#25034]
 
 26.5
 -----

WordPress/Classes/Utility/BuildInformation/FeatureFlag.swift

@@ -1,5 +1,6 @@
 import BuildSettingsKit
 import Foundation
+import FoundationModels
 
 /// FeatureFlag exposes a series of features to be conditionally enabled on
 /// different builds.
@@ -80,8 +81,10 @@ public enum FeatureFlag: Int, CaseIterable {
         case .newStats:
             return false
         case .intelligence:
-            let languageCode = Locale.current.language.languageCode?.identifier
-            return (languageCode ?? "en").hasPrefix("en")
+            guard #available(iOS 26, *) else {
+                return false
+            }
+            return SystemLanguageModel.default.supportsLocale()
         case .newSupport:
             return false
         case .nativeBlockInserter: