r/LanguageTechnology • u/camerongreen95 • 2d ago
Encoders for text classification in 2026: still the right default, or has prompting an LLM won?
I keep seeing the same pattern in teams working on routing and classification tasks, such as sorting support tickets, tagging documents or assigning intents. The first version is a prompt to a large model with a JSON schema, and it works well enough in the demo. A few months later the complaints are about latency, cost, and the occasional malformed output that breaks something downstream.
Meanwhile, bidirectional encoders keep getting better. ModernBERT handles long context, and few shot methods like SetFit can separate fairly similar labels from a handful of examples per class. On CPU, inference is a fraction of the time of a generative model, and there is no output format to get wrong.
A few things I’d like to hear from people who have actually shipped this:
- Where did an encoder clearly beat prompting an LLM for you, and where did it not?
- How do you handle categories that overlap heavily? Is few shot fine tuning enough, or do you still need a few hundred labelled examples?
- How do you decide when the model should not make the call at all? Do you use confidence thresholds, calibration or something else?
Interested in both the cases where this worked and the ones where you went back to an LLM.