/api/tomtom/flow was the only keyed, billed proxy left outside the cross-site gate added in #900. Every uncached tile is an upstream attempt counted against the persistent daily budget, so any web page the user visits could fire <img> requests at distinct z8-z16 tiles, spend the TomTom quota and leave the traffic layer on 429 budget for the rest of the UTC day. Gate both routes with admitSameSite, like the Places routes.
TOMTOM_DAILY_TILE_BUDGET defaulted to 40,000 per day against a free
tier that is granted per MONTH, not per day. TomTom currently allows
200,000 Traffic Flow & Incidents tile requests per month
(https://docs.tomtom.com/pricing/), so the default exhausted a user's
entire monthly allowance in five days and left the traffic layer dead
for the rest of the billing period.
The docs contradicted themselves on this. traffic.js described the
free tier as "~50k/day", while .env.example cited the correct 200K
per month two lines below quoting the same 40,000 default. 50k/day
would be 1.5M/month, 7.5x the actual allowance.
Sets the default to 6,000/day. A 31-day month lands at 186,000,
inside the allowance with headroom. Corrects the stale figures in
traffic.js, .env.example and DATA_SOURCES.md.
This remains an application-side safety ceiling, not a billing cap,
and the surrounding text still says so. TomTom's free tier requires
no card, so overrunning it cuts the layer off rather than generating
a charge — but a layer that dies three weeks into every month is
still worth avoiding by default.
Co-Authored-By: Claude Opus 5 <[email protected]>