Lists the response documents received for an invoice, oldest first. A response document is a file another party sent back about your invoice. The source field identifies the channel each document arrived through.

Documents received on the invoice exchange network (source: network):

• French PPF cross-domain acknowledgement responses (CDARs) reporting the invoice's lifecycle statuses.
• Peppol application responses (buyer acceptance/rejection).
• EDI rejection notices.
• Italian SDI ricevute, including the mancata consegna (failed delivery) notice.

Documents issued by a tax authority about the invoice's tax reports (source is the authority's transport code):

• fr.dgfip: PPF acknowledgements of French e-reporting submissions (acknowledged / registered / refused).
• pl.ksef: the KSeF UPO, Poland's official receipt of registration.

Reports for other tax authorities do not contribute response documents yet. Download the original file through attachment.download_url; attachment is null when the response was recorded without a file. Responses addressed to a whole ledger (batch submission) are not listed here — retrieve those with the ledger's download_response endpoint. The collection is always returned complete, without pagination: an invoice accumulates at most a handful of response documents.