Summary titles generated in English despite German transcript and de-DE locale

[hyper-charlie]

Description

Summary titles are consistently generated in English even when the meeting transcript is in German and the user's locale is set to de-DE.

Steps to Reproduce

1. Conduct or upload a meeting with German audio/transcript
2. Allow Hyprnote to generate an AI summary
3. Observe the summary title language

Expected Behavior

Summary titles should match the transcript language and user locale (German in this case)

Actual Behavior

Summary titles are generated in English while the full summary content is correctly in German

Environment

• Platform: macOS (aarch64)
• OS Version: macOS 26.3.1
• App Version: 1.0.16
• Build: c212379
• Locale: de-DE
• User: lukas@possnigg-consulting.at

Notes

• This occurs consistently across all German transcripts
• Full summary content is generated in German—only the title is in English
• Expected behavior: titles should be generated in the same language as the transcript/user locale

[devin-ai-integration]

Codebase Investigation

Root Cause Analysis

The title generation pipeline does support language-aware prompts, but the language may not be reaching the prompt correctly depending on the user's ai_language setting state. Here's the full data flow:

How Title Generation Works

1. Trigger: After a successful enhance (summary) task, enhance-success.ts automatically starts a title generation task (apps/desktop/src/store/zustand/ai-task/task-configs/enhance-success.ts:40-44).

2. Args Transform: title-transform.ts reads ai_language from the settings store and passes it as the language field (apps/desktop/src/store/zustand/ai-task/task-configs/title-transform.ts:17-23):

   function getLanguage(settingsStore: SettingsStore): string | null {
     const value = settingsStore.getValue("ai_language");
     return typeof value === "string" && value.length > 0 ? value : null;
   }

3. System Prompt: title-workflow.ts renders the Jinja template with the language arg (apps/desktop/src/store/zustand/ai-task/task-configs/title-workflow.ts:50-62).

4. Template: title.system.md.jinja uses a language filter to convert the code to a language name (crates/template-app/assets/title.system.md.jinja:5):

   - You are a professional assistant that generates a perfect title for a meeting note, in {{ language | language }} language.
   

5. Language filter (crates/askama-utils/src/filters.rs:28-33): When language is None, defaults to English:

   pub fn language(value: &Option<String>, ...) -> askama::Result<String> {
       let raw = value.as_deref().unwrap_or("").to_lowercase();
       let v = extract_iso639(&raw);
       let lang = Language::from_639_1(v).unwrap_or(Language::from_639_1("en").unwrap());
       Ok(lang.to_name().to_string())
   }

The Likely Issue

The ai_language setting default is "en" (defined in apps/desktop/src/store/tinybase/store/settings.ts:59-63). While there is an auto-detection mechanism via getPreferredLanguages() in the settings persister (apps/desktop/src/store/tinybase/persister/settings/persister.ts:16-28), it only applies defaults when ai_language is null:

if (language.ai_language == null && defaults.ai_language) {
    language.ai_language = defaults.ai_language;
}

The problem: The schema default is "en" (not null), so by the time the persister runs, ai_language is already "en" from the TinyBase schema default — meaning the OS locale detection never overrides it for existing users who didn't explicitly change this setting.

Even though the enhance (summary body) system prompt uses the same getLanguage() function and the same ai_language setting, the summary content may still appear in German because the LLM naturally follows the language of the input transcript. Titles are generated from the enhanced note content rather than the raw transcript, and the system prompt explicitly instructs "in English language" — so the LLM obeys that instruction more strictly for the short title output.

Relevant Files

File	Role
apps/desktop/src/store/zustand/ai-task/task-configs/title-transform.ts	Reads ai_language from settings
apps/desktop/src/store/zustand/ai-task/task-configs/title-workflow.ts	Constructs the LLM prompt
crates/template-app/assets/title.system.md.jinja	Title system prompt template
crates/askama-utils/src/filters.rs	language filter (defaults to English)
apps/desktop/src/store/tinybase/store/settings.ts	ai_language default = "en"
apps/desktop/src/store/tinybase/persister/settings/persister.ts	OS locale auto-detection logic
apps/desktop/src/store/zustand/ai-task/task-configs/enhance-success.ts	Triggers title generation after enhance

Potential Fix Approaches

1. Check if ai_language was explicitly set by the user vs defaulted: If it's still the schema default "en" and the OS locale is de-DE, prefer the OS locale.
2. Change the schema default for ai_language from "en" to empty/null: This would allow the OS locale detection in the persister to kick in on first load for all users.
3. Add transcript language detection: Infer the language from the transcript/enhanced note content and pass it to the title prompt regardless of the ai_language setting.

[goranmoomin]

This should be fixed in commit 92172ab. Will be able to close this once the fix gets into releases.