Phase State Machine vs Freeform ReAct Loop: Why Structured Agents Don't Hallucinate
The traditional ReAct (Reason + Act) prompting pattern is notorious for getting stuck in infinite loops, jumping prematurely into code edits, and failing to verify results. Smoke Monkey Harness replaces freeform loops with a deterministic 6-phase engineering state machine.
Phase State Machine vs Freeform ReAct Loop: Why Structured Agents Don't Hallucinate: The traditional ReAct (Reason + Act) prompting pattern is notorious for getting stuck in infinite loops, jumping prematurely into code edits, and failing to verify results. Smoke Monkey Harness replaces freeform loops with a deterministic 6-phase engineering state machine. Designed as a zero-dependency, open-source TypeScript architecture under the MIT License with native Model Context Protocol (MCP) support and deterministic phase state machines.
- The Flaw of ReAct: Models act without planning and fail without recovering.
- The 6 Engineering Phases: explore → plan → edit → verify → recover → complete.
- Restricted Toolsets per Phase: An agent cannot edit files during the `explore` phase or declare completion during `verify`.
Phase Breakdown and Invariants
- Explore: Tools restricted to
view_file,list_dir,grep_search. - Plan: Task decomposition and rollback strategies.
- Edit:
write_to_fileandreplace_file_content. - Verify: Test and linter execution via
run_command. - Recover: Activated on test failure; synthesizes adjustments.
- Complete: Generates git diffs and session persistence.
Frequently Asked Questions
Q:Can the agent transition backward from verify to edit?
Yes! If `verify` fails, the state machine transitions to `recover`, which diagnoses the error before returning to `edit`.
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Zero dependencies. 24 built-in tools. Human-in-the-loop safety. 100% open source under the MIT License.