Self-RAG

Problem

Static retrieve-then-generate pipelines retrieve regardless of whether retrieval is needed, and they generate regardless of whether the retrieved evidence is actually relevant or whether the generation is grounded in it. Cheap queries that did not need retrieval still pay for it. Bad retrievals still feed the generator. Ungrounded generations still ship to the user. Without explicit reflective steps where the model decides whether to retrieve, judges the relevance of what it retrieved, and checks whether its own draft is supported by the evidence, the system both wastes calls and quietly admits hallucinations into production.

Solution

A critic model is first trained to label data with reflection tokens. The generator is then fine-tuned on the labeled data to emit four reflection tokens inline at inference: [Retrieve], [IsRel] (is retrieved evidence relevant?), [IsSup] (is generation supported?), [IsUse] (is generation useful?). The host enforces the reflection grammar and uses tokens to control flow.

When to use

• Retrieval-augmented generation needs to decide when to retrieve and whether evidence is relevant.
• Static retrieve-then-generate wastes calls or admits hallucination.
• Fine-tuning the model with reflection tokens is feasible.