PS4 Notifications Mod and his GTA V Native Caller, today PlayStation 4 developer @2much4u detailed some PS4 System Notification Types for 4.05 Firmware via Twitter for devs as outlined below.
Download: PS4_405_System_Notification_Types.txt / PS4 GTA V Native Caller
To quote from the Github page: Message types for sceSysUtilSendSystemNotification functions on PS4 version 4.05
1: Unknown USB device connected.
2: Too many USB hubs connected.
3: Connect this device using a USB cable, or connect it again.
4: %s battery level low.
5: %s disconnected.
6: Too many USB devices connected.
7: Cannot connect another Bluetooth device.
9: Cannot connect another controller.
10: Cannot connect another mouse or keyboard.
11: Cannot use controller feature of keyboard.
12: Device not supported.
13: Cannot use wireless controllers for PS3.
14: %s connected their companion app.
15: %s disconnected their companion app.
16: %s connected using Remote Play.
17: %s disconnected from Remote Play.
18: %s cannot see the screen due to Remote Play blocked scene.
19: %s can see the screen again because Remote Play blocked scene ended.
22: Less than %s free in system storage.
23: LAN cable not connected.
24: Wi-Fi network connection lost.
25: Cannot connect to network.
26: %s logged in to PS4.
28: Your account is banned from PlayStation Network.
29: PlayStation Network access from this PS4 banned or temporarily suspended.
30: Update the system software.
31: PlayStation Network is currently busy.
32: PlayStation Network is currently undergoing maintenance.
33: PlayStation Network is no longer available.
35: Sign in to PSN to use network features.
36: Signed out of PSN.
37: Update application to use network features.
38: Update system software to use network features.
39: PlayStation Network features in this application unavailable due to age restrictions.
40: Application will expire in %s minutes.
41: Application suspending in %s minutes because license cannot be verified.
42: Party chat audio prioritized.
43: Game chat audio prioritized.
45: Cannot use voice chat with %s, possibly due to NAT type.
46: Kicked out of party.
47: No longer in party due to network error.
48: Cannot take screenshot now.
49: This is a blocked scene for gameplay recording.
50: Cannot display menu now.
51: Only microphone audio is being broadcast.
53: Broadcast stopped.
54: Song playback stopped.
56: The PS4 automatically turned off due to power save settings.
57: Only 4 users can be logged in at the same time.
58: Deleted because you already have %s Bluetooth devices registered.
59: Message sent.
60: To switch to your screen, press the PS button.
61: Gameplay recording paused because you entered blocked scene.
62: Gameplay recording resumed because you exited blocked scene.
63: -Snapshot Icon-
64: -Recording Icon-
66: Chat audio switched to game.
67: Chat audio switched to party.
69: Chat audio also muted for players on same PS4 as %s.
71: Cannot connect to server, so network features for this application unavailable.
73: Confirming your licenses for using content on this PS4.
74: This ad will end soon.
75: %s disconnected. Charge the battery.
77: %s disconnected. Charge the battery.
78: Gameplay is currently not being recorded.
79: %s joined the party. (Players: )
80: %s left the party. (Players: )
81: You are now party owner.
82: Broadcast paused.
83: Video clip saved.
84: Microphone not connected.
85: Both microphone audio and gameplay are being broadcast.
86: Broadcast ends in %s minutes.
87: Broadcasting only microphone audio because you entered a blocked scene.
88: Broadcast paused because you entered a blocked scene.
89: Broadcasting gameplay and microphone audio because you exited a blocked scene.
90: Game closing in %s minutes due to inactivity.
91: Game closed due to inactivity.
93: Game closing in %s minutes because time limit will be reached.
94: Server maintenance starts in %s hours.
97: Game closing soon because server maintenance starts in %s minutes.
98: Screenshot saved.
99: Network features for this application temporarily unavailable.
100: Game closed due to insufficient internet connection quality.
101: Cannot start game.
102: Game closed because PS Now game was started on another device.
103: Game closed because connection to server was lost.
104: Game closed because time limit was reached.
105: Game closed due to server maintenance.
106: %s suggested players to invite to your party.
107: Cannot connect another audio device.
108: Broadcast started, and will end in %s.
109: Microphone for PS camera muted, so players in party cannot hear you.
110: The BD remote control is not supported by the PS4.
111: Broadcast resumed.
112: Broadcasting resumed because you exited blocked scene.
113: Game closing in 1 minute due to inactivity.
114: Insufficient free space to record your gameplay.
115: Server maintenance starts in %s minutes.
117: PS Now game closing due to insufficient internet connection.
118: Use the controller that was just connected.
119: Gameplay recording is temporarily paused.
120: You cannot control the system now.
121: Cannot operate PS4 with voice now.
122: This USB device's file system is unsupported.
123: Feature unavailable for visitors.
124: Cannot connect another USB device.
126: Cannot find face.
127: Cannot find face because PS Camera is already in use.
128: Share Play started as host.
129: %s is connecting to your PS4 to join Share Play.
130: Visitor cannot see game screen when you view non-game screens.
131: You joined share play with %s (host).
132: Visitor cannot see game screen due to blocked scene.
133: Visitor can see game screen again.
134: Cannot control Share Play game now.
135: Visitor cannot control game due to restricted scene.
136: Visitor can control game again.
137: Share Play stops in %s minutes.
138: Share Play will stop in 1 minute.
139: Visitor cannot use selected feature.
140: Controller given to visitor.
142: You can now play as host.
143: You can now play together with host.
144: Controller taken back by %s (host).
145: %s (visitor) left Share Play.
146: Cannot display all songs because there are more than %s.
148: Microphone switched to microphone for PS Camera.
149: Microphone switched to headset connected to controller.
151: Microphone switched to USB microphone.
152: Microphone switched to USB headset.
153: Microphone switched to Bluetooth headset.
154: Restart your PS4.
157: %s could not connect to your PS4.
158: Microphone switched to microphone on VR headset.
159: Cannot use audio device you just connected while using VR headset.
160: Cannot use this USB storage device.
161: Gameplay recording paused.
162: Gameplay recording resumed.
163: Gameplay recording currently paused.
164: Screen resolution changed by application.
165: Information posted.
166: Could not post information.
167: Visitor cannot play or see game until you return to it.
168: Invitation sent to %s.
169: Private party created and invitation sent to %s.
170: Keypad disconnected.
171: Cannot use keypad because too many mice or keyboards are connected.
173: No microphone that you can use.
174: All users' microphones switched to microphone on PS Camera.
176: PS Camera disconnected, so now no users have a microphone.
177: Insufficient free space to take screenshots.
178: Controller type changed.
179: Controller type changed, and you can play as host.
180: Controller type changed, and you can play together with host.
181: An event is about to start for the following user. -Subtext-%s
183: Cannot add one or more players.
184: Cannot change group name.
185: Cannot change group image.
186: Cannot add group to [Favorite Groups].
187: Cannot delete group from [Favorite Groups].
188: Cannot leave group.
189: Cannot listen to music in the background while using Remote Play.
190: Cannot listen to music in the background while broadcasting.
191: Cannot listen to music in the background while using Share Play.
192: Group added to [Favorite Groups].
194: Invitations sent to players.
197: Request sent to %s.
198: Group deleted from [Favorite Groups].
199: Cannot create new group.
200: Group already added to [Favorite Groups].
201: Cannot use another USB audio device while using VR headset.
202: Virtual surround sound of the audio headset is temporarily disabled.
203: -No Notification-
204: Review surroundings and clear any obstacles before use. See important health and safety warnings in the Settings menu.
205: Start this game now to join a game session more quickly.
207: Cannot add some players because of their settings.
208: Party invitation sent to group.
209: Private party created and invitation sent to group.
210: %s connected.
211: Following %s.
212: Cannot change the limit on the number of players.
213: Group created.
214: Cannot add some players because of their settings.
216: Cannot share event with message group.
217: Cannot share event with Community.
218: Cannot use audio features of this device.
219: Cannot use audio features of some devices.
220: Activity shared.
221: Cannot share activity.
223: Player blocked.
224: Cannot send message.
225: High-resolution captures unsupported by this application are not displayed.
226: Song playback stopped because you reached the monthly free time limit.
232: 3D audio of the audio headset is temporarily disabled.
233: Players suggested to the party owner for invitation.
234: Private party created and invitations sent to players.
235: Song added to [Your Music].
236: Song removed from [Your Music].
237: Cannot add song to [Your Music].
238: Cannot remove song from [Your Music].
239: Your account is suspended from PlayStation Network.
240: You have left the party.