Configure lei to search against an external (an inbox or external
index). When C<LOCATION> is an existing local path, it should point
-to a directory that is a C<public.<name>.inboxdir> or
-C<extindex.<name>.topdir> value in ~/.public-inbox/config.
+to a directory that is a C<publicinbox.$NAME.inboxdir> or
+C<extindex.$NAME.topdir> value in ~/.public-inbox/config.
=head1 OPTIONS
=item --mirror=URL
Create C<LOCATION> by mirroring the public-inbox at C<URL>.
+C<LOCATION> will have a Makefile with a C<make update>
+target to update the external.
+
+=item --epoch=RANGE
+
+Restrict clones of L<public-inbox-v2-format(5)> inboxes to the
+given range of epochs. The range may be a single non-negative
+integer or a (possibly open-ended) C<LOW..HIGH> range of
+non-negative integers. C<~> may be prefixed to either (or both)
+integer values to represent the offset from the maximum possible
+value.
+
+For example, C<--epoch=~0> alone clones only the latest epoch,
+C<--epoch=~2..> clones the three latest epochs.
+
+Default: C<0..~0> or C<0..> or C<..~0>
+(all epochs, all three examples are equivalent)
=item -v
=item --no-torsocks
-Whether to wrap L<git(1)> and L<curl(1)> commands with torsocks.
+Whether to wrap L<git(1)> and L<curl(1)> commands with L<torsocks(1)>.
Default: C<auto>
=item --inbox-version=NUM
-Force a public-inbox version (must be C<1> or C<2>).
+Force a remote public-inbox version (must be C<1> or C<2>).
+This is auto-detected by default, and this option exists mainly
+for testing.
=back