Pattern
Dual-Locale Portuguese Without Dual Hallucinations
Treat PT-BR and PT-PT as separate product surfaces—tagging, filters, and eval splits so one locale’s phrasing does not poison the other.
1 min readJaneiro.ai
Shared language is not shared product. PT-BR and PT-PT diverge in register, entities, and buyer expectation—and mixed indexes blur both.
The pattern
Run dual-locale Portuguese as two surfaces, one system.
- Tag every chunk and prompt with
pt-BRorpt-PTat ingest and eval time. - Filter retrieval by locale before rank; do not “average” Lusophone evidence.
- Keep separate golden slices so a Lisbon tone win cannot mask a São Paulo entity failure.
When to use
- Products serving both Brazil and Portugal (the corridor)
- Knowledge bases that mix EU and Brazilian policy or catalog copy
- Teams that previously shipped one “Portuguese” string file
- Stacks that now include a PT-PT-first model such as Amália beside a Brazil-tuned path
Trade-offs
- More metadata and a slightly larger eval suite
- Avoids confident answers that sound right in the wrong market
- Respects the corridor without treating it as one bloc
One language family. Two product surfaces. Zero blended hallucinations.
portugueseragcorridor
Published by Janeiro.ai. Original editorial for operators. How this was made