2000-line prompt + 30 tools was too slow: LangGraph + plain code fixed this fraud agent
colinmcnamara · x · 2026-11-10
Joseph Fluckiger shared his fraud-detection agent rework at AIMUG Austin:
- Original setup: one 2,000-line prompt driving 30 MCP tools; a single run took about four minutes and was non-deterministic.
- The fix: a LangGraph flow where plain code pre-processes raw MCP calls, passing only the signal the agent actually needs.
- Result: much faster and far more deterministic runs.
The full talk is available online; the next AIMUG meetup is Monday, Dec 7, free, in Austin and online.
Related event: Engineer Rebuilds 2,000-Line Prompt Fraud Agent with LangGraph for Speed(2 posts)→
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