Dev.to
6/27/2026

The original title is "Inside An AI Agent: Planning, Tool Use, Memory, Constraints, And Verification"
Original: Inside An AI Agent: Planning, Tool Use, Memory, Constraints, And Verification
Short summary
Production agents aren't magic — they're software workflows where LLMs pick the next step and call tools. Success depends on five core pillars: planning (thinking before acting), tool use (safe orchestration), memory (state tracking), constraints (budget and iteration limits), and verification (output checking). The post breaks down each pillar with TypeScript/Python examples and compares plan-then-execute vs. ReAct approaches.
- •Agents are workflows around planning, tool use, memory, constraints, and verification — not magic
- •Plan-then-execute vs. ReAct represent different tradeoffs between cost/latency and adaptability
- •Production agents need auditable plans, constraint guards, and output verification before shipping
Generated with AI, which can make mistakes.
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