Business Context

Northstar Systems uses an internal LLM assistant for HR, IT, and finance workflows such as ticket routing, policy Q&A, and email drafting. Prompt quality is inconsistent across teams, so you need to design and evaluate a prompt optimization pipeline for task-specific enterprise use cases.

Data

You have 180,000 historical prompt-response pairs collected from internal usage logs across 12 tasks. Inputs range from 20-1,200 words, with a median of 180 words. Text is primarily English, but about 9% includes mixed-language content, copied email threads, bullet lists, tables, and internal acronyms. Human preference labels are available for 35,000 examples, with pairwise rankings and task-specific quality annotations such as factuality, format compliance, and actionability. Label quality is uneven across teams.

Success Criteria

A good solution improves task success rate by at least 12% over the current baseline prompts, reduces invalid or off-format outputs below 3%, and keeps median inference latency under 2 seconds. The system should generalize across tasks without requiring full model fine-tuning for every workflow.

Constraints

• Prompts must not expose confidential data beyond the minimum required context
• The solution must run in a private cloud environment
• Prompt templates must be versioned, testable, and easy for non-ML teams to update
• Token budget is limited to 4,096 tokens per request

Requirements

1. Define a prompt optimization approach for multiple enterprise tasks
2. Build a preprocessing pipeline for noisy internal text and task metadata
3. Implement a modern Python workflow for prompt generation, scoring, and evaluation
4. Explain how you would compare prompt variants using offline and online metrics
5. Describe failure modes such as hallucination, prompt injection, and formatting drift
6. Recommend how to operationalize prompt versioning, rollback, and monitoring