#^/bms/transactions/(?P<source>trucking|transload|chassis|scale-ticket)$# accepts POST and is declared in app/systems/BMS/transaction/api_routes.php:137 as a regex pattern.
The route handler delegates to bmsTransactionApiAccount(). That function is the owner of
this behaviour; the route entry is only dispatch.
No literal caller path was found in frontend/, public/ or new-system/.
The endpoint may be called through a constructed path, a helper wrapper, or only by
an external client. Treat the route table and owner function as the authority.
The response is produced by a shared helper, so the key set is not visible at the
route. Read the owner function to confirm the shape before writing a client.
These strings come from the owner function and are the messages a client can
receive. They are also the cheapest way to tell a rejected request from a broken one.