Configure for one hop only

The FAQ talks about this.

You should let people choose their path length.

Right now the path length is hard-coded at 3 plus the number of nodes in your path that are sensitive. That is, in normal cases it's 3, but for example if you're accessing an onion service or a ".exit" address it could be 4.

We don't want to encourage people to use paths longer than this — it increases load on the network without (as far as we can tell) providing any more security. Remember that the best way to attack Tor is to attack the endpoints and ignore the middle of the path. Also, using paths longer than 3 could harm anonymity, first because it makes "denial of security" attacks easier, and second because it could act as an identifier if only a few people do it ("Oh, there's that person who changed her path length again").

And we don't want to encourage people to use paths of length 1 either. Currently there is no reason to suspect that investigating a single relay will yield user-destination pairs, but if many people are using only a single hop, we make it more likely that attackers will seize or break into relays in hopes of tracing users.

Now, there is a good argument for making the number of hops in a path unpredictable. For example, somebody who happens to control the last two hops in your path still doesn't know who you are, but they know for sure which entry node you used. Choosing path length from, say, a geometric distribution will turn this into a statistical attack, which seems to be an improvement. On the other hand, a longer path length is bad for usability, and without further protections it seems likely that an adversary can estimate your path length anyway. We're not sure of the right trade-offs here. Please write a research paper that tells us what to do.

This is disallowed by all standard relays in the network. There used to be a AllowSingleHopCircuits option that relays could set to allow this, but it was removed several years ago.