Fix: a recommended GTFS file is missing

Published: 3 July 2026. Last reviewed: 3 July 2026.

Code: missing_recommended_file (MobilityData validator)

What this means

GTFS has required files and recommended ones. This finding means a recommended file is absent from the feed. In practice it is almost always feed_info.txt, the file that names the publisher and states the feed's validity dates.

Why it matters

feed_info.txt tells apps who publishes the feed, in what language, and when it expires. Without it, no app can warn a rider that your data is going stale, and a developer who finds a problem has no stated owner to contact. It is a small file that does a lot of quiet work, which is why the spec recommends it even though it is not strictly required.

How to fix it

Add the missing file. For feed_info.txt, include:

• feed_publisher_name and feed_publisher_url,
• feed_lang,
• feed_start_date and feed_end_date (the validity window).

Most scheduling tools can write feed_info.txt from an export setting once you enter the publisher details. If the finding names a different recommended file, the same idea applies: look for the matching export option, or add the file to the export.

How long it usually takes

A one-time setup in export settings. After the publisher details are entered the file ships on every run.

Authoritative rule

missing_recommended_file is a canonical MobilityData GTFS Validator notice used in validator reports across the GTFS ecosystem. Read the authoritative rule for missing_recommended_file in the GTFS Validator rules. (opens on an external site)