40 protobuf files, 775 messages and 75 enums (both counts include nested types). Every file in this build declares no package, so the group below is derived from the file name: demo.proto is Demo; a name ending in gameevents or usermessages is that family; the files that carry the core connection, channel and entity-delta protocol (netmessages, networkbasetypes, usercmd, te, and seven more) are CS2 wire format; a name for a GC channel, a Steam message set, or Steam Datagram Relay is GC and Steam SDK; everything left over is Other. Only the first four groups are the CS2 game's own wire format; the rest ship in the same descriptor set because the client links against the Steam client and GC libraries, not because CS2 speaks them over its own connection.
CS2 build 25218825 · Steam date 2026-09-09 · platform windows-x86_64 · schema format 2.2
| File | Messages | Enums | Imports | Description |
|---|
| c_peer2peer_netmessages.proto | 7 | 2 | netmessages, networkbasetypes | |
| clientmessages.proto | 6 | 2 | | |
| connectionless_netmessages.proto | 3 | 0 | netmessages | |
| cs_prediction_events.proto | 2 | 1 | networkbasetypes, prediction_events | |
| cs_usercmd.proto | 4 | 0 | valveextensions, networkbasetypes, usercmd | |
| netmessages.proto | 74 | 12 | networkbasetypes, source2_steam_stats | Core Source 2 network protocol messages exchanged between client and server. Includes server-info negotiation, entity delta updates, string tables, voice data, and game-event delivery. Client→Server messages use the CLC_ prefix; Server→Client use SVC_. |
| network_connection.proto | 0 | 1 | google/protobuf/descriptor | |
| networkbasetypes.proto | 27 | 3 | valveextensions, google/protobuf/descriptor, network_connection | Foundational proto-type definitions shared across all CS2 network and game-event messages. Provides compact vector, angle, quaternion, colour, and player-info structs used as fields in higher-level messages. |
| networksystem_protomessages.proto | 5 | 0 | | |
| te.proto | 25 | 1 | networkbasetypes | |
| usercmd.proto | 5 | 0 | valveextensions, networkbasetypes | |
Demo
Game events
| File | Messages | Enums | Imports | Description |
|---|
| cs_gameevents.proto | 5 | 1 | networkbasetypes | CS2-specific game event protobuf messages. These are temporary entity (TE) events and game events broadcast from the server to clients that are within the relevant PVS or listening for the event type. Identified by the ECsgoGameEvents enum (450–453). |
| gameevents.proto | 18 | 1 | networkbasetypes | Source 2 base game-event protobuf messages. Provides the Source 1-legacy game-event bridge (CMsgSource1LegacyGameEvent), sound-system events (SoS), and surface-decal events. Identified by the EBaseGameEvents enum (200–212). |
User messages
| File | Messages | Enums | Imports | Description |
|---|
| cstrike15_usermessages.proto | 90 | 2 | networkbasetypes, cstrike15_gcmessages | CS2 user-messages sent reliably from server to one or more clients. These messages carry HUD feedback, audio triggers, economy updates, and kill-cam data. They are identified by the ECstrike15UserMessages enum (IDs 301–388). |
| usermessages.proto | 107 | 5 | networkbasetypes | |
GC and Steam SDK
Other