Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so every parameter (id, text, model, autoRun, budgetUsd, mediaKeys) is already documented in the schema, including the 4000-char limit and model list. The description only alludes to 'files attached' (mediaKeys) and adds nothing further, so the baseline 3 applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.