diff --git a/tracker/models/models.go b/tracker/models/models.go
index 89df300..e48388c 100644
--- a/tracker/models/models.go
+++ b/tracker/models/models.go
@@ -43,13 +43,18 @@ type NotFoundError ClientError
 func (e ClientError) Error() string   { return string(e) }
 func (e NotFoundError) Error() string { return string(e) }
 
+// PeerList represents a list of peers: either seeders or leechers.
 type PeerList []Peer
+
+// PeerKey is the key used to uniquely identify a peer in a swarm.
 type PeerKey string
 
+// NewPeerKey creates a properly formatted PeerKey.
 func NewPeerKey(peerID string, ip net.IP, port string) PeerKey {
 	return PeerKey(peerID + "//" + ip.String() + ":" + port)
 }
 
+// IP parses and returns the IP address for a given PeerKey.
 func (pk PeerKey) IP() net.IP {
 	ip := net.ParseIP(strings.Split(string(pk), "//")[1])
 	if rval := ip.To4(); rval != nil {
@@ -58,10 +63,16 @@ func (pk PeerKey) IP() net.IP {
 	return ip
 }
 
+// PeerID returns the PeerID section of a PeerKey.
 func (pk PeerKey) PeerID() string {
 	return strings.Split(string(pk), "//")[0]
 }
 
+// Port returns the port section of the PeerKey.
+func (pk PeerKey) Port() string {
+	return strings.Split(string(pk), "//")[2]
+}
+
 // Peer is a participant in a swarm.
 type Peer struct {
 	ID        string `json:"id"`
@@ -79,14 +90,19 @@ type Peer struct {
 	LastAnnounce int64  `json:"last_announce"`
 }
 
+// HasIPv4 determines if a peer's IP address can be represented as an IPv4
+// address.
 func (p *Peer) HasIPv4() bool {
 	return !p.HasIPv6()
 }
 
+// HasIPv6 determines if a peer's IP address can be represented as an IPv6
+// address.
 func (p *Peer) HasIPv6() bool {
 	return len(p.IP) == net.IPv6len
 }
 
+// Key returns a PeerKey for the given peer.
 func (p *Peer) Key() PeerKey {
 	return NewPeerKey(p.ID, p.IP, string(p.Port))
 }