# Message Schema Index

JSON Schema (draft 2020-12) definitions for the IRC-style message protocol.

All messages share a common envelope defined in
[`message.schema.json`](message.schema.json).

## Base Envelope

| Field     | Type            | Required | Description |
|-----------|-----------------|----------|-------------|
| `command` | string          | ✓        | IRC command name or numeric reply code |
| `from`    | string          |          | Sender nick or server name |
| `to`      | string          |          | Destination channel or nick |
| `params`  | array\<string\> |          | Additional IRC-style parameters |
| `body`    | array \| object | varies   | Message body (never a raw string) |
| `meta`    | object          |          | Extensible metadata (signatures, etc.) |
| `id`      | string (uuid)   |          | Server-assigned message ID |
| `ts`      | string (date-time) |       | Server-assigned timestamp |

## Client-to-Server (C2S)

| Command  | Schema | Description |
|----------|--------|-------------|
| PRIVMSG  | [`c2s/privmsg.schema.json`](c2s/privmsg.schema.json) | Send message to channel or user |
| NOTICE   | [`c2s/notice.schema.json`](c2s/notice.schema.json) | Send a notice |
| JOIN     | [`c2s/join.schema.json`](c2s/join.schema.json) | Join a channel |
| PART     | [`c2s/part.schema.json`](c2s/part.schema.json) | Leave a channel |
| QUIT     | [`c2s/quit.schema.json`](c2s/quit.schema.json) | Disconnect |
| NICK     | [`c2s/nick.schema.json`](c2s/nick.schema.json) | Change nick |
| MODE     | [`c2s/mode.schema.json`](c2s/mode.schema.json) | Set/query modes |
| TOPIC    | [`c2s/topic.schema.json`](c2s/topic.schema.json) | Set/query topic |
| KICK     | [`c2s/kick.schema.json`](c2s/kick.schema.json) | Kick user |
| PING     | [`c2s/ping.schema.json`](c2s/ping.schema.json) | Client keepalive |
| PUBKEY   | [`c2s/pubkey.schema.json`](c2s/pubkey.schema.json) | Announce public key |

## Server-to-Client (S2C)

### Named Commands

| Command  | Schema | Description |
|----------|--------|-------------|
| PRIVMSG  | [`s2c/privmsg.schema.json`](s2c/privmsg.schema.json) | Relayed message |
| NOTICE   | [`s2c/notice.schema.json`](s2c/notice.schema.json) | Server or user notice |
| JOIN     | [`s2c/join.schema.json`](s2c/join.schema.json) | User joined channel |
| PART     | [`s2c/part.schema.json`](s2c/part.schema.json) | User left channel |
| QUIT     | [`s2c/quit.schema.json`](s2c/quit.schema.json) | User disconnected |
| NICK     | [`s2c/nick.schema.json`](s2c/nick.schema.json) | Nick change |
| MODE     | [`s2c/mode.schema.json`](s2c/mode.schema.json) | Mode change |
| TOPIC    | [`s2c/topic.schema.json`](s2c/topic.schema.json) | Topic change |
| KICK     | [`s2c/kick.schema.json`](s2c/kick.schema.json) | User kicked |
| PONG     | [`s2c/pong.schema.json`](s2c/pong.schema.json) | Server pong |
| PUBKEY   | [`s2c/pubkey.schema.json`](s2c/pubkey.schema.json) | Relayed public key |
| ERROR    | [`s2c/error.schema.json`](s2c/error.schema.json) | Server error |

### Numeric Replies

| Code | Name               | Schema | Description |
|------|--------------------|--------|-------------|
| 001  | RPL_WELCOME        | [`s2c/001.schema.json`](s2c/001.schema.json) | Welcome after registration |
| 002  | RPL_YOURHOST       | [`s2c/002.schema.json`](s2c/002.schema.json) | Server host info |
| 322  | RPL_LIST           | [`s2c/322.schema.json`](s2c/322.schema.json) | Channel list entry |
| 353  | RPL_NAMREPLY       | [`s2c/353.schema.json`](s2c/353.schema.json) | Names list |
| 366  | RPL_ENDOFNAMES     | [`s2c/366.schema.json`](s2c/366.schema.json) | End of names list |
| 372  | RPL_MOTD           | [`s2c/372.schema.json`](s2c/372.schema.json) | MOTD line |
| 375  | RPL_MOTDSTART      | [`s2c/375.schema.json`](s2c/375.schema.json) | Start of MOTD |
| 376  | RPL_ENDOFMOTD      | [`s2c/376.schema.json`](s2c/376.schema.json) | End of MOTD |
| 401  | ERR_NOSUCHNICK     | [`s2c/401.schema.json`](s2c/401.schema.json) | No such nick/channel |
| 403  | ERR_NOSUCHCHANNEL  | [`s2c/403.schema.json`](s2c/403.schema.json) | No such channel |
| 433  | ERR_NICKNAMEINUSE  | [`s2c/433.schema.json`](s2c/433.schema.json) | Nick in use |

## Server-to-Server (S2S)

| Command | Schema | Description |
|---------|--------|-------------|
| RELAY   | [`s2s/relay.schema.json`](s2s/relay.schema.json) | Relay message to linked server |
| LINK    | [`s2s/link.schema.json`](s2s/link.schema.json) | Establish server link |
| UNLINK  | [`s2s/unlink.schema.json`](s2s/unlink.schema.json) | Tear down link |
| SYNC    | [`s2s/sync.schema.json`](s2s/sync.schema.json) | Synchronize state |
| PING    | [`s2s/ping.schema.json`](s2s/ping.schema.json) | Server ping |
| PONG    | [`s2s/pong.schema.json`](s2s/pong.schema.json) | Server pong |