Reducing unsupported answers by making the system respond only when evidence is clearly present in the source text.
Current Workflow
The user enters a 3GPP RAN/RRC question.
The primary BM25 retriever searches the local TS 38.331 PDF.
The system retrieves the top chunks using top_k = 8.
The system selects up to 18 evidence sentences from the retrieved chunks.
The generator produces an answer using only the selected evidence.
The NLI judge checks whether the answer is supported by the evidence.
If the answer is supported, the system returns the answer.
If the answer is weak or unsupported, the system runs adaptive retrieval over a fixed list of selected 5G/RRC sources.
The generator tries again using adaptive evidence.
The NLI judge checks the adaptive answer.
If the adaptive answer is still unsupported, the system returns:
Not enough information.
NLI Judge
The updated system uses:
cross-encoder/nli-deberta-v3-base
The judge compares the generated answer with the selected evidence. It looks at entailment, contradiction, and support.
The judge can return verdicts such as:
supported
partially supported
unsupported
This makes the system more evidence-aware because the final answer is not accepted only because retrieval found some related text. The generated answer must also be checked against the evidence.