OpenWeather One Call API vs Stormglass API

OpenWeather One Call API

1,000 free calls a day, then $0.0015 a call, or $0.001 on the agent lane. The main API takes the key only as the appid query parameter.

Stormglass API

A read-only weather and marine API with about 70 hourly parameters, per-source values from named national models, tide data and ERA5 history from 2014. No OpenAPI file, status page, SDK or security page was found, the free plan allows 10 requests a day, and the docs and FAQ disagree on the status code for a spent quota.

OpenWeather One Call API

1. Sign up on the agent lane with POST https://agents.openweathermap.org/v1/accounts and keep the data key. It's shown once
2. Check GET https://data.openweathermap.org/account/balance for credit. No data response carries a cost or balance
3. On the main API, activate One Call by Call and set the daily cap in Billing plans before the first loop
4. Pass units=metric. The default is Kelvin
5. Use exclude=minutely,alerts on 3.0, or the 4.0 timeline step you need, to shrink responses

Stormglass API

1. Send the key as Authorization: KEY with no Bearer prefix. A missing or wrong key returns 403 with {"errors":{"key":"API key is invalid"}}
2. Always pass source=sg or a short source list on /weather/point. The default is every source, which multiplies the size of each hourly record
3. Treat 402 as a spent daily quota, not a billing failure, and stop until the next day. Read meta.requestCount against meta.dailyQuota on each response
4. Use /historical/point for past dates, at most 10 days a call and nothing newer than about 7 days. /weather/point looks back 14 days only
5. Send and read all times in UTC. Tide sea levels are relative to the chosen datum (MSL by default) and are not water depth