Draft language mismatch

[elie222]

User description

Ensure auto-generated drafts match the email thread's language by adding explicit instructions to AI prompts and new language-specific tests.

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Linear Issue: INB-37

 

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Generated description

Below is a concise technical summary of the changes proposed in this PR:
Ensures that AI-generated email replies and follow-ups match the language of the existing conversation by updating system prompts. Introduces automated tests to verify language detection and response generation in Spanish, French, and German.

Topic	Details
Language Logic	Update the systemPrompt in aiDraftReply and aiDraftFollowUp to explicitly instruct the AI to detect and match the thread's language. Modified files (2) apps/web/utils/ai/reply/draft-follow-up.ts apps/web/utils/ai/reply/draft-reply.ts Latest Contributors(0) User Commit Date
Language Testing	Add comprehensive test cases to validate that the AI correctly generates responses in Spanish, French, and German when provided with non-English email threads. Modified files (2) apps/web/__tests__/ai/reply/draft-follow-up.test.ts apps/web/__tests__/ai/reply/draft-reply.test.ts Latest Contributors(0) User Commit Date

This pull request is reviewed by Baz. Review like a pro on (Baz).

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Project	Deployment	Review	Updated (UTC)
inbox-zero	Ready	Preview	Jan 20, 2026 7:38pm

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