✈ Discuss your project
All case studies / AI Assistants & Agents

LLM parts search audit cuts query cost by 16.7% without losing accuracy

Industry: Auto parts marketplaceFocus: AI assistants and agents
−16.7%cost per query: $0.1353 → $0.1128
0OEM numbers lost on the control set after optimization
3 stagesaudit, accuracy improvements, cost reduction; all paid
I need something similar

Before

  • The client asked for an analysis of accuracy issues in their AI-powered auto parts search and a plan for improvements
  • Search built on Node.js: LLM in Yandex AI Studio plus web search, without a vector index or reference database
  • Payment for cost reduction was tied to the measured percentage of savings

What we built

  • Pipeline audit: query understanding, sources and their trust levels, candidate extraction and ranking
  • Benchmark setup: reference query set, exact@1, hit@5, MRR metrics, repeated runs to account for noise
  • Vehicle generation detection by VIN and part compatibility checks were implemented
  • Cost: removed an unnecessary 23.7 thousand-character knowledge base from the system prompt, compressed JSON, deduplicated queries, cached the static prefix
  • Every change passed an accuracy gate; a shortened prompt reduced accuracy and was rolled back

How it works

QueryVIN or text
→
NormalizationLLM parses the query
→
Web searchsources with trust levels
→
Extraction and rankingOEM number candidates
→
Benchmark setupaccuracy and cost of each run

Before and after

WhatBeforeAfter
Query cost$0.1353$0.1128
Cached prompt tokens0173 thousand

Result

  • The audit was accepted and the client closed the order
  • The improvements and cost reduction were paid for, and acceptance documents were signed
  • The benchmark caught a reranker regression before production deployment, and the change was rolled back

Technology

Node.jsTypeScriptPythonYandex AI Studiocustom accuracy benchmark
What matters in a project like this. The main cost was not web requests (31%), but model tokens (69%). Query deduplication saved exactly zero, while prompt cleanup and prefix caching produced the savings.

Have a similar project?

Describe it in two lines in Telegram. We'll explain how we'd approach it, how long it would take, and what it would cost.

Message me on Telegram

Similar case studies