Where to find documentation about the log reader procedures?

From the replication monitor in sql server transactional replication, when I have a look at what has been replicated, from publisher to the distributor, I get the following picture: It does not show on the replication monitor, therefore running the internal procedures to get hold of what has been read from the transaction log and replicated to the distributor I use the following procedure: use [master] exec [distribution]..sp_MSenum_logreader_sd @name = N'myserver-Product-102', @time = N'20170410 16:36:16.917' this gives me the following results: (same data as on the picture above, plus more information) **Question:** I am struggling to find any documentation on the stored procedure that I use to find out what the log reader agent has been doing: **sp_MSenum_logreader_sd** where can I find information about this procedure? I also would like to save this info into a temp table or table variable, so that when I spot an error_id that is not zero I can get extra info as you can see below, based on the error_id from the picture above. -- error_id 5467351 comes from the above result set use [master] exec [distribution]..sp_MSget_repl_error @id = 5467351