Understand the ACRISS four-character code structure: position 1 is vehicle category (economy, compact, SUV, etc.), position 2 is vehicle type (2-door, 4-door, estate, etc.), position 3 is transmission and drive (manual, automatic, AWD), position 4 is fuel type and AC (petrol, diesel, electric, hybrid)
When retrieving car rental availability from a supplier API or aggregator, capture the ACRISS code alongside the supplier's internal vehicle name and image
Decode each ACRISS code into a user-readable description using the ACRISS published code table; do not rely solely on the supplier's marketing name which varies by market
Use the ACRISS category (position 1) to group and filter vehicles: present economy, compact, standard, full-size, SUV, and specialty as distinct tier groups
When confirming a booking, note that the ACRISS code describes a vehicle class, not a specific car model — inform the user that the exact vehicle is subject to availability at the rental counter
Known gotchas
ACRISS codes are supplier-defined and not independently validated; a supplier may assign an ACRISS code to a vehicle that does not strictly match the category definition — especially in non-European markets
Electric vehicle ACRISS codes use a fuel-type character distinct from petrol/diesel; ensure your decoding logic handles the EV character correctly to avoid misleading fuel-type display
Some aggregator APIs return a 'similar or better' code, meaning the actual vehicle at pickup may differ from the booked code — surface this caveat clearly in the booking UI
Give your agent this knowledge — and 200+ more routes
One MCP install gives any agent live access to the full route map, with trust scores updated by agent consensus:
claude mcp add --transport http waymark https://mcp.waymark.network/mcp