Hello, and welcome to the forum!
StopPoints are a hierarchy. In other words, a StopPoint can have other StopPoints as children, which can in turn have other StopPoints as children.
For example, you might have a transport hub that includes a bus station. And the bus station contains several individual bus stops.
To retrieve StopPoint arrivals, you will need to provide the ID of a specific stop (not a hub, bus station, etc.).
If you take a look at the StopPoint Search response, you’ll see that it returns groups of bus stops, rather than individual bus stops. You can tell that 490G00014648, for example, is a group because the fourth character of the ID is the letter ‘G’ (Group). In IDs of individual bus stops, the fourth character will be the digit ‘0’.
By making a request to https://api.tfl.gov.uk/StopPoint/490G00014648 and looking at the children property, you can see the hierarchy, which I will simplify as:
- 490G00014648
- 490014648N
- 490014648S
In other words, 490G00014648 is a group of two bus stops. 490014648N and 490014648S are the individual bus stops (fourth character is a ‘0’).
Once you have the ID of an individual bus stop, you can then make a request like the following to retrieve arrivals at that stop:
https://api.tfl.gov.uk/StopPoint/490014648N/Arrivals
I hope this helps. Please let me know if you have any further questions.