Errors/Chain errors
OutputBufferTooSmall
Check the argument values against the operation schema
The output buffer the contract supplied to an API call is smaller than the data the runtime needs to write back. Check the output length pointer the contract passes and enlarge the buffer; usually a contract-side bug.
Declared by the Contracts pallet; it classifies to the semantic code invalid_argument.
Remediation
Check the argument values against the operation schema
The same explanation is available in the terminal: btcli explain OutputBufferTooSmall.