Agent( )

Pattern

Structured Agent Output: Output.choice

Demonstrate structured agent outputs using ToolLoopAgent with Output.choice. Constrain agent outputs to predefined choices for predictable, type-safe responses.

IntermediateNov 2025View the full pattern on desktop
Structured Agent Output: Output.choice preview

Problems solved

  • Constrain ToolLoopAgent output to Output.choice options
  • Return predictable enum-like agent answers
  • Combine constrained outputs with tool-calling agents

Use cases

  • Recommendation agents with fixed option sets
  • Triage bots that must pick from known labels
  • Form-like agent decisions
  • Guaranteed-format agent API responses

AI SDK APIs

ToolLoopAgentOutput.choiceagent.generatetool

Tags

aiagentsstructured-outputstool-loop-agentoutput-choiceai-sdkagent-api

Requirements

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

Environment variables

External services

openai

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