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Systems & state

The hardest bugs live between steps

In draft Draft date

A sequence of reasonable actions can still produce an unreasonable result — the transitions deserve their own tests

Working outline — full essay forthcoming

Rough outline

Choose a boundary failure

  • Sketch a state transition that makes two correct components fail together
  • Use an illustrative workflow and label it clearly

Inspect the handoff

  • Check assumptions about ordering, freshness, ownership, and retries
  • Distinguish stale state from incorrect logic

Test transitions deliberately

  • Inject interruptions, duplicate responses, and partially completed actions
  • Assert invariants across steps rather than checking outputs in isolation

Connect the career threads

  • Add a real game or integration-testing example that illustrates the pattern
  • Explain how the same reasoning changes an agent architecture