[README] Mention peerindex inside utilities section

README.md

@@ -32,8 +32,8 @@ Extensive documentation of `lonetix` and its API is available.
 
 # Utilities
 
-`lonetix` is the building block of `bgpgrep`, this far our single
-utility - but more of them are coming, right?
+`lonetix` is the building block of `bgpgrep` and `peerindex`, this far our
+only two utilities - but more of them are coming, right?
 
 `bgpgrep` performs fast and reliable analysis of MRT dumps
 collected by most Route Collecting projects. It takes a different
@@ -42,6 +42,10 @@ filtering utilities, in order to extrapolate only relevant data
 out of each MRT dump (and incidentally save quite some time).
 In-depth documentation of `bgpgrep` is available in its man page.
 
+`peerindex` allows to quickly inspect the peer index table record inside
+MRT TABLE_DUMP_V2 RIBs. Just like `bgpgrep`, documentation is
+available in a dedicated man page.
+
 # Building
 
 The Micro BGP Suite uses [Meson](https://mesonbuild.com/) to manage its build