Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so both parameters (apiKey, amountUsd) are already fully documented in the schema, including the key-omission guidance. The description adds only the framing that the key is 'the calling Bearer API key', which is marginal; baseline 3 applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.