Ext · Cross-cutting
Loop Detection
Detects when agents get stuck repeating the same sequence of actions. Uses multiple detection methods from hash-based to semantic clustering.
Examples
- Agent calls search_tool("weather") 15 times in a row with identical queries
- Agent A asks B for clarification, B asks A, creating endless back-and-forth
- Agent paraphrases the same response 8 times using different wording
- State oscillates between two values without converging on a solution
Detection methods
- Structural Matching
- Detects repeated action sequences via substring matching
- Hash Collision
- Identifies identical state hashes indicating no progress
- Semantic Clustering
- Groups semantically similar messages using embeddings
- Summary Whitelisting
- Distinguishes recap/progress patterns from genuine loops
Calibration accuracy
F1
0.846
Precision
0.829
Recall
0.863
From the Pisama calibration set. See detector scoreboard for the full table.
Detect this in production with the framework adapters (LangGraph, CrewAI, AutoGen, OpenAI Agents SDK, Claude Agent SDK, n8n, Dify). See the full taxonomy at /taxonomy.