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FlowChat

Regex-powered chat processor for Minecraft. Replace, filter, toast, auto-respond, and play sounds on chat messages -- works on clients and servers across every major platform. Current version: 2.1.2.

Platforms

Platform	Type	Versions
Fabric	Client mod	1.14.4 - 1.21.11
Forge	Client mod	1.7.10 - 1.21.11
NeoForge	Client mod	1.20.4 - 1.21.11
Spigot/Paper	Server plugin	1.7.10 - 1.21.11
BungeeCord	Proxy plugin	Latest
Velocity	Proxy plugin	Latest

Features

• Regex replacement -- Match incoming chat with regex, replace with formatted text
• Outgoing message rules -- Intercept and rewrite messages you send (command aliases, color prefixing)
• Color-aware matching -- colorAware: true matches against text with color codes preserved; replacements support &a, &l, etc.
• Toast notifications -- Redirect matched messages from chat to overlay display ("toast": true)
• Notification styles -- "notifyStyle": "actionbar" (default), "toast" (system toast), or "advancement" (achievement popup)
• Sound alerts -- Play sounds on match: "sound": true (default sound), "sound": "bell" (specific sound), or "sound": "note_pling"
• Auto-responses -- Send a command/message when a pattern matches: "respond": "/cmd" (single) or "respond": ["/cmd1", "/cmd2"] (multi)
• JSON matching -- matchJson: true matches against raw JSON chat components instead of displayed text
• Value stacking -- Aggregate numeric capture groups across rapid messages into running totals
• Tag selectors -- {player}, {time}, {biome}, {item_name}, and 389 more expanded in replacements
• Server filtering -- "server": "^mc\\.example\\.com" restricts a rule to matching servers only
• Message cancellation -- Set replacement to pleasecancelthismessage to hide a message from chat entirely
• Hot-reload -- Edit rules file without restarting the game or server
• Legacy field support -- Old field names (search, toastMe, respondMsg, serversearch, msgsearch, msgreplacement) still work via aliases

Rule Format

{
  "incoming": [
    { "pattern": "hello", "replacement": "world" },
    { "pattern": "alert_me", "toast": true, "sound": "bell", "notifyStyle": "advancement" },
    { "pattern": "greet", "respond": ["/say Hi!", "/say Welcome!"] }
  ],
  "outgoing": [
    { "pattern": "/b", "replacement": "/bottle get 64" }
  ]
}

Value Stacking

Aggregates numeric capture groups across rapid successive messages. When a shop sends multiple lines quickly (e.g. selling items in bulk), value stacking collapses them into a running total.

Token	Meaning
$1, $2, ...	Standard regex group references (current match only)
$^1, $^2, ...	Stacked value for that group (accumulated total)
$^i	Iteration count (how many messages stacked)

Installation

Client: Download the JAR for your MC version and loader from Releases. Drop it in your mods/ folder. FlowChat creates a default config at .minecraft/config/flowchat.json on first launch.

Server: Download the server JAR (Spigot, Bungee, Velocity, or Unified) from Releases. Drop it in plugins/. For 1.14.4+ servers, install PacketEvents for packet-level chat interception (optional -- falls back to Bukkit events).

Reload: Edit flowchat.json and run /flowchat reload in-game. No restart needed.

Links

• GitHub
• CurseForge
• Full config reference