Can I assume that the a:b value equals to <PROJECT_ID>:<PROJECT_SECRET>
The params value will need to be Array of ChainEpoch (integer) or TipSetKey (string) 2 items. In your example, you have an array of strings and integers.
Are you getting back any response from the request? If so can you help to share the full response message with us?
@Lily using the format [ 407137, 40137 ] I’m getting this error:
{"jsonrpc":"2.0","id":0,"error":{"code":-32700,"message":"unmarshaling params for 'Filecoin.ChainGetTipSetByHeight' (param: *types.TipSetKey): json: cannot unmarshal number into Go value of type []cid.Cid"}}
I’m also getting the same issue (no response) in other methods like StateMarketDeals