VoiceOS confirmation cards only show args that have a matching data-voiceos-key field; alias args stay invisible

In a VoiceOS (local MCP) integration, the confirmation widget script fills each field from the tool args by key: for every element with data-k-key or data-voiceos-key, it copies args[key] if that key is present. Any argument without a field never appears on the card, but the server still receives it and acts on it.

Seen Nov 2026 on an Excel integration. The append-rows tool accepted both table_id and table_name (the server uses table_id || table_name), but the card only had a table_id field. The agent sent table_name, so the card showed an empty Table ID and the user approved rows into a table they never saw. The chart tool had the same problem with worksheet_name and series_by.

Fix: give every write argument that changes the target or the outcome a field on its card. Or drop the alias args from the inputSchema. Cheap guard test: for each tool with a confirmation, assert every inputSchema property has a matching data-voiceos-key in confirmation.root.html, with an explicit allowlist for args like drive_id, or aliases a required field overrides on the server.