Agent( )
Pattern
INT·Jun 26

Loop Control: stopWhen

Demonstrate ToolLoopAgent loop control with stopWhen. Covers stepCountIs, hasToolCall, combined conditions, and a custom StopCondition with step timeline visualization.

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Loop Control: stopWhen preview

Problems Solved

  • Control agent loop length with stepCountIs
  • Stop agent loops when a specific tool is called
  • Combine multiple stopWhen conditions
  • Implement custom StopCondition logic
  • Inspect agent steps and tool calls after a run

Use Cases

  • Limit runaway agent tool loops
  • Stop when a completion tool is invoked
  • Budget agent steps in production workflows
  • Custom termination based on step history

AI SDK APIs

ToolLoopAgentstopWhenstepCountIshasToolCallStopConditiontoolgateway

Tags

aiagentsloop-controlstop-whenstep-count-ishas-tool-calltool-loop-agentai-sdkagent-api

Requirements

Node.js
24+
Memory
512MB
Other
  • OpenAI API key

Environment Variables

External Services

openai

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End of Pattern