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LLMs, GenAI, RAG, agents, evaluation · insight-0529

Repair failed outputs with the validator's error message and a retry cap

Evidence type
practitioner heuristic
Difficulty
easy
Roles
Applied AI, ML engineer
Industries
cross-industry

Summary: situation, action, reason, boundary

  1. Situation

    A structured extraction fails business-rule validation on a few percent of documents, and an engineer adds code that silently coerces bad values into defaults.

  2. Action

    On validation failure, re-prompt once or twice with the original input, the failed output and the specific validator error; if it still fails, mark the record as failed and send it to review; log attempt counts.

  3. Reason

    A concrete error message is external feedback the model can act on, while coercion destroys the signal that something went wrong.

  4. Boundary

    Extraction and transformation pipelines with automatic validators.

Symptom or risk

Coerced defaults look like real data, hide the failure rate and corrupt downstream analytics.

Exceptions

When failures cluster on one input type, fix the prompt or schema instead of relying on retries.

Trade-offs

Each retry adds latency and cost; caps keep them bounded.

Pitfalls

Retrying without telling the model what was wrong, which often reproduces the same output.

Lessons and concepts