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Testing & agents

A useful failure needs a replay

In progress Draft date

The value of a failure depends partly on whether another engineer can investigate it

Working outline — full essay forthcoming

Rough outline

Define a useful failure record

  • Capture task inputs, context, tool responses, versions, and event ordering
  • Separate sensitive data from the diagnostic information that must be retained

Distinguish replay from reproduction

  • Explain what can be replayed exactly and what may vary across model calls
  • Record the limits of the evidence rather than promising determinism

Design the investigation workflow

  • Freeze external responses and inspect intermediate decisions
  • Minimize the case until the causal boundary becomes clear

Make replay part of development

  • Attach a compact replay case to a bug report
  • Turn a resolved failure into an appropriately scoped regression check