Fix: recommended fields left empty

Code: missing_recommended_field (MobilityData validator)

What this means

A file in the feed is missing a field the spec recommends, one apps rely on

even though the feed still loads without it. Common examples: agency_lang,

stop_desc alternatives, or feed_info contact fields. The validator's

notice names the exact file and field for your feed.

Why it matters

Recommended fields are where rider experience lives. The feed works without

them, but apps show less: no contact link when a rider needs help, wrong

language assumptions, poorer stop descriptions. Filling them costs little and

each one shows up directly in what riders see.

How to fix it

• Read the notice for the exact field. The validator names the file and

column; the fix is filling that column.

• Most scheduling tools have a home for these values (agency profile,

feed settings, stop attributes); fill it there so every future export

carries it.

• If the tool has no home for it, a one-time edit of the exported file

works, but push your vendor to carry the value so it survives the next

export.

How long it usually takes

Minutes per field once you find where your tool stores it. The value usually

already exists somewhere in your agency; this is copying it into the export.

Authoritative rule

missing_recommended_field is a canonical MobilityData GTFS Validator notice, the same rule behind the statewide GTFS quality reports. Read the authoritative rule for missing_recommended_field in the GTFS Validator rules. (opens on an external site)