One model request the scripted mock received, flattened to text for assertions — the seam that lets a harness test prove what reached the model (a SessionStart hook's injected context, a slash command's expansion), not just that a hook fired.
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The conversation messages, each flattened to { role, text }.
{ role, text }
The system prompt, flattened to text (string or text-block array).
One model request the scripted mock received, flattened to text for assertions — the seam that lets a harness test prove what reached the model (a SessionStart hook's injected context, a slash command's expansion), not just that a hook fired.