chat_grid/docs/item-types.md

Item Types

This is behavior-focused documentation for item types and their defaults.

Shared Item Behavior

• Items are server-authoritative.
• Global per-type fields are injected by the server and are not persisted per-instance:
  • capabilities
  • useSound
  • emitSound
  • useCooldownMs (from item catalog)
  • emitRange (spatial range in squares)
  • directional (directional attenuation enabled)
• Instance fields are persisted in server/runtime/items.json.

radio_station

Defaults

• Title: radio
• Params:
  • streamUrl=""
  • enabled=true
  • mediaChannel="stereo"
  • mediaVolume=50
  • mediaEffect="off"
  • mediaEffectValue=50
  • facing=0
  • emitRange=20
• Global:
  • useSound=none
  • emitSound=none
  • useCooldownMs=1000
  • emitRange=20
  • directional=true

Use

• use toggles enabled on/off and broadcasts chat status.

Validation

• mediaChannel: stereo | mono | left | right
• mediaVolume: integer 0..100
• mediaEffect: reverb | echo | flanger | high_pass | low_pass | off
• mediaEffectValue: number 0..100 with 0.1 precision
• facing: number 0..360 with step 1
• emitRange: integer 5..20

dice

Defaults

• Title: Dice
• Params:
  • sides=6
  • number=2
• Global:
  • useSound=sounds/roll.ogg
  • emitSound=none
  • useCooldownMs=1000
  • emitRange=15
  • directional=false

Use

• Rolls number dice with sides sides and reports values + total.

Validation

• sides: integer 1..100
• number: integer 1..100

wheel

Defaults

• Title: wheel
• Params:
  • spaces="yes, no"
• Global:
  • useSound=sounds/spin.ogg
  • emitSound=none
  • useCooldownMs=4000
  • emitRange=15
  • directional=false

Use

• Announces spin immediately.
• Result is sent after delay.

Validation

• spaces: comma-delimited values
• At least 1 entry
• Max 100 entries
• Max 80 chars per entry

clock

Defaults

• Title: clock
• Params:
  • timeZone="America/Detroit"
  • use24Hour=false
• Global:
  • useSound=none
  • emitSound=sounds/clock.ogg
  • useCooldownMs=1000
  • emitRange=10
  • directional=false

Use

• Reports current time from item timezone and format.

Validation

• timeZone: one of CLOCK_TIME_ZONE_OPTIONS in server/app/item_catalog.py
• use24Hour: boolean or on/off style input

widget

Defaults

• Title: widget
• Params:
  • enabled=true
  • directional=false
  • facing=0
  • emitRange=15
  • emitVolume=100
  • emitSoundSpeed=50
  • emitSoundTempo=50
  • emitEffect="off"
  • emitEffectValue=50
  • useSound=""
  • emitSound=""
• Global:
  • useSound=none
  • emitSound=none
  • useCooldownMs=1000
  • emitRange=15
  • directional=false
  • emitSoundSpeed=50
  • emitSoundTempo=50

Use

• use toggles enabled on/off and plays useSound when configured.

Validation

• enabled: boolean or on/off style input
• directional: boolean or on/off style input
• facing: number 0..360 with step 1
• emitRange: integer 1..20
• emitVolume: integer 0..100
• emitSoundSpeed: integer 0..100 (0=0.5x, 50=1.0x, 100=2.0x) for speed/pitch
• emitSoundTempo: integer 0..100 (0=0.5x, 50=1.0x, 100=2.0x) for tempo
• emitEffect: reverb | echo | flanger | high_pass | low_pass | off
• emitEffectValue: number 0..100 with 0.1 precision
• useSound: empty, filename (assumed under sounds/), or full URL
• emitSound: empty, filename (assumed under sounds/), or full URL

piano

Defaults

• Title: piano
• Params:
  • instrument="piano"
  • voiceMode="poly"
  • octave=0
  • attack=15
  • decay=45
  • release=35
  • brightness=55
  • emitRange=15
• Global:
  • useSound=none
  • emitSound=none
  • useCooldownMs=1000
  • emitRange=15
  • directional=false

Use

• Announces that the user begins playing the piano (client enters piano key mode).
• Piano mode controls include , to start/stop recording (max 30s) and . to play saved recording.
• Recordings are stored on the item (server-authoritative), so nearby users hear playback.

Validation

• instrument: piano | electric_piano | guitar | organ | bass | violin | synth_lead | brass | nintendo | drum_kit
• voiceMode: poly | mono
• octave: integer -2..2
• attack: integer 0..100
• decay: integer 0..100
• release: integer 0..100
• brightness: integer 0..100
• emitRange: integer 5..20
• Instrument changes reset voiceMode/octave/attack/decay/release/brightness to instrument defaults.

Adding A New Item Type (Plugin Discovery)

Server is the source of truth for item type definitions and metadata. The client consumes server welcome.uiDefinitions and only provides UX/runtime behavior.

For a full copy/paste example with plain-English explanation, see docs/item-type-template.md.

1. Server item package: add a new folder under server/app/items/types/<item_type>/ with:
   • definition.py (defaults/capabilities/metadata/options)
   • validator.py (validate_update)
   • actions.py (use_item)
2. Server plugin: add server/app/items/types/<item_type>/plugin.py exporting ITEM_TYPE_PLUGIN with:
   • type
   • order
   • module The server auto-discovers plugins at boot, so no central registry edit is needed.
3. Server/client protocol/state models are now string-based for item type ids; for generic types no enum/union list updates are required.
4. Client runtime behavior: add client/src/items/types/<item_type>/behavior.ts only if custom client runtime is needed (for example piano mode).
5. Tests: add or update server tests under server/tests/ for use/update validation, unknown-key stripping, and uiDefinitions completeness.

Example Shape

A minimal new item type usually needs:

• Catalog defaults:
  • default_title
  • default_params
  • use_sound / emit_sound
  • use_cooldown_ms
• Handler behavior:
  • validate params on update
  • build self/others use messages
  • optionally return delayed result text