The tool retries after timeout. How to prevent repeated sending of letters, repeated orders or repeated publishing?

Handle the uncertain results of external side effects with stable operation flags, parameter summaries, and result queries.

Idempotentside effectsTry againNot sure about the result

Knowledge content check2026-10-03 · Check the source of the original question2026-10-02

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Principles and Solutions have been collapsed. Explain the core mechanism, boundaries and verification methods in your own words, and then compare them.

Answers and personal notes

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Explain in your own words first

The core principles, analysis, Q&A and migration cases have been closed. When you are ready, unfold it and compare it with the content to find any omissions.

Hands-on verificationComplete on demand · Suggestions15 minutes

Demonstrates a recovery process when publishing is successful but the response is lost.

Expand acceptance requirements and checkpoints

Don’t blindly re-post
Business key stable across retries
Not declared successful or not executed when it cannot be verified

Key inspections

Distinguish between unexecuted, executed and unknown results
Duplicate requests with the same key and different parameters with the same key are clearly handled
It can explain that local transactions cannot guarantee that remote side effects are exactly once