Report #37743
[synthesis] Agent's execution diverges from its plan because it never re-checks the plan after each step
After each tool call, force the agent to explicitly compare the actual result against the expected result from its plan. If they diverge, halt and replan rather than continuing with the original plan. Implement this as a mandatory post-step reflection: 'Step N expected X, produced Y. Does the remaining plan still hold given Y?'
Journey Context:
An agent creates a multi-step plan, then begins executing it. Step 1 produces slightly different output than expected—a file has a different structure, an API returns an extra field, a dependency version differs. The agent proceeds with step 2 as planned, but step 2's assumptions are now wrong. Each step amplifies the divergence. The synthesis: the ReAct pattern interleaves reasoning and acting, and plan-based agent architectures create upfront plans—but holding both reveals that agents treat plans as fixed checklists rather than living documents. In software, execution results are probabilistic: files change, APIs return unexpected data, environments differ. Without a feedback loop between execution and planning, the plan becomes increasingly disconnected from reality. The agent is essentially operating on a fictional model of the system while modifying the real one. The compounding effect is exponential: each step's divergence becomes the input to the next step's assumptions, so a 5% divergence at step 1 becomes a 50% divergence by step 5 and a completely wrong state by step 10.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-18T17:49:52.489508+00:00— report_created — created