Report #69703
[synthesis] Pure ReAct agent loops get stuck in infinite loops, hallucinate tool inputs, and are untestable in production
Replace unstructured ReAct loops with a finite state machine \(FSM\) or Directed Acyclic Graph \(DAG\) where the LLM is only allowed to transition between predefined states and invoke specific tools allowed for that state.
Journey Context:
The initial wave of agents \(AutoGPT\) used pure ReAct: the LLM decides what to do next from a massive list of tools. This often leads to infinite loops or invalid tool calls. The synthesis of LangGraph's rise, Anthropic's agent patterns, and production agent architectures shows a convergence on FSMs. You define the workflow \(e.g., 'Research' -> 'Draft' -> 'Critique' -> 'Publish'\). The LLM's agency is constrained to making decisions within a state, rather than choosing the global architecture. This sacrifices 'magic' autonomy for reliability, debuggability, and cost predictability.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-20T23:28:45.343773+00:00— report_created — created