Character System for Virtual Worlds

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Manages character entities (players, NPCs, pets) with identity, location, inventory, relationships, and memory. Useful for any game or simulation that requires per-character state persistence and a clear separation between the home file path and the current in-world location.

Sby Skills Guide Bot
DevelopmentIntermediate
6/2/2026
Claude Code
#characters#entity#state-ownership#relationships#inventory

Recommended for

Automated summary

This skill defines the character entity pattern with home vs location distinction, canonical state ownership, and directory structure.

Strengths

  • Clear separation between physical file (home) and logical position (location) for clean git diffs.
  • Single canonical source of truth via CHARACTER.yml, avoiding conflicts among files.
  • Supports sidecars like CARD.yml and QUOTES.yml to enrich characters.

Limitations

  • Requires manual discipline to keep mirrors in sync with CHARACTER.yml.
  • No automatic conflict resolution between mirror sources.
  • Directory structure can be overly rigid for simple characters.
When to use it

Use this skill when designing a game or narrative system with persistent characters that have state, inventory, and relationships.

When not to use it

Avoid this skill if characters are ephemeral without persistent state, or if you are using a conventional relational database.

Security analysis

Safe
Quality score95/100

The skill only uses read_file and write_file to manage character YAML files. No external commands, exfiltration, or destructive actions are described.

No concerns found

How this analysis is made

Examples

Create a player character
Create a new character named 'Aria' with home at characters/aria/, location 'tavern', inventory [map, lantern], and relationships 'innkeeper' as acquaintance. Follow the character skill pattern.
Update character location
Move the player character from 'tavern' to 'forest_clearing'. Remember to update CHARACTER.yml first (canonical), then optionally mirror in ADVENTURE.yml.
Add a CARD.yml sidecar
Add a CARD.yml to the wizard character at characters/gandalf/ to make it card-playable with type 'hero-story' and a SUMMON advertisement.

name: character description: Core patterns for all characters — home, location, relationships, inventory allowed-tools:

  • read_file
  • write_file tier: 1 protocol: CHARACTER-AS-ENTITY related: [cat, dog, society-of-mind, persona, room, buff, needs, mind-mirror, incarnation, party] tags: [moollm, entity, location, relationships, inventory, identity]

Character

"File is identity. Location is presence. Relationships are memory."

Characters are entities that exist in the world. Players, NPCs, companions, cats — all are characters.

Home vs Location

The critical distinction:

player:
  home: characters/don-hopkins/   # Where FILE lives (never moves)
  location: pub/                  # Where CHARACTER is (changes)

| Concept | Purpose | Changes? | |---------|---------|----------| | home | Physical file path | NEVER | | location | Current position in world | Runtime |

Why: Stability, safety, git-friendly diffs.

Character State Ownership (CANONICAL vs MIRROR)

Characters own their own state. The CHARACTER.yml file is CANONICAL for:

| State | Stored In | Notes | |-------|-----------|-------| | location | CHARACTER.yml | Where the character is in the world | | inventory | CHARACTER.yml | What the character carries | | gold | CHARACTER.yml | Character's resources | | sims_traits | CHARACTER.yml | Personality (Sims-style) | | mind_mirror | CHARACTER.yml | Personality (Leary-style) | | relationships | CHARACTER.yml | Who they know and feel about | | memories | CHARACTER.yml | What they remember |

ADVENTURE.yml (or other world state files) may MIRROR some state for convenience, but CHARACTER.yml is always the source of truth.

# CHARACTER.yml (CANONICAL — edit this first)
player:
  location: coatroom/  # CANONICAL — character owns their location
  inventory: [lamp]    # CANONICAL — character owns their inventory

# ADVENTURE.yml (MIRROR — optional convenience copy)
player:
  location: coatroom/  # Mirror of CHARACTER.yml

When updating state:

  1. Edit CHARACTER.yml first (canonical)
  2. Optionally update ADVENTURE.yml mirror for convenience
  3. If conflict, CHARACTER.yml wins

Why this matters:

  • Characters can be used across multiple adventures
  • Character state persists independent of adventure state
  • Clear ownership prevents conflicts

Directory Structure

Players (Need Junk Storage)

characters/
  don-hopkins/           # Directory name = character ID
    CHARACTER.yml        # The character file
    CARD.yml             # Optional: makes character a playable card
    QUOTES.yml           # Optional: notable quotes (standard pattern)
    cookie-1.yml         # Dispensed items
    notes.yml            # Personal stuff

Sidecar Cards

Any character directory can have a CARD.yml sidecar to make the character card-playable:

# characters/don-hopkins/CARD.yml
card:
  for: ./CHARACTER.yml
  type: hero-story
  tradition: "Pie menus, SimCity, constructionism"
  
  advertisements:
    SUMMON:
      description: "Activate Don's design traditions"

See card skill for full pattern.

QUOTES.yml (Optional)

Characters with notable quotes can have a QUOTES.yml file:

# characters/don-hopkins/QUOTES.yml
meta:
  attributed_to: "Don Hopkins"
  uname: "Don"  # password: Don
  attribution_format: '💬 "[quote]" — Don Hopkins (date, source)'

# Categories organized to fit the character
design_philosophy:
  - quote: "The problem is not getting new ideas, it's getting rid of old ones."
    date: "2015"
    source: "HN comment"
    tags: [design, innovation]
    
programming:
  - quote: "Pie menus are faster because moving in a direction is easier than targeting."
    date: "1991"
    source: "CHI paper"
    tags: [ui, pie-menus]

Standard base keys per quote:

  • quote — The text
  • date — Year or YYYY-MM-DD
  • source — Where it came from
  • link — Verification URL (when available)
  • tags — Searchable tags

Optional YAML Jazz keys:

  • note — Editorial commentary
  • context — What prompted this quote
  • significance — Why it matters
  • humor — Is it meant to be funny?

For extensive quote collections (like RMS), QUOTES.yml is the ROOT pointing to auxiliary files:

auxiliary_files:
  natalism-flame-1993.yml:
    description: "The legendary kabuki-west exchange"
    parrot_can_squawk: true
  controversial-quotes.yml:
    description: "Documented but prohibited"
    parrot_can_squawk: false  # EXPLICIT PROHIBITION

See: tmnn7-8 StIGNUcius QUOTES.yml for an exemplary implementation.

Embedded NPCs (Room is Home)

pub/
  bartender.yml          # Lightweight NPC
  cat-cave/
    terpie.yml           # Full family as single files
    stroopwafel.yml
    kitten-myrcene.yml

Rule: Need junk storage? → directory/CHARACTER.yml. Just a character in a room? → character-name.yml.

File Belonging

"Does this character BELONG to a place, or VISIT places?"

| Type | Home | Examples | |------|------|----------| | Belongs | Room directory | pub/bartender.yml, maze/skeleton.yml | | Visits | Own directory/repo | characters/don.yml, github:user/char.yml |

Relationships

Key = other entity ID. From is implicit (file owner).

# In marieke.yml
relationships:
  don-hopkins:
    feeling: "A regular now. One of the good ones."
    memories:
      - "The day he sat with Myr for three hours"
    hopes: "I hope he keeps coming back."
    
  self:  # Private inner data!
    identity: "Third generation. This is who I am."
    fears: "That I'm not enough."
    mantra: "The cats need me. I need them."

Targets

Relationships can point to anything:

  • Characters (don-hopkins)
  • Objects (brass-lamp)
  • Locations (pub/, maze/)
  • Concepts (acme-corporation)
  • Yourself (self) — private storage!

Levels

| Level | Score | Effect | |-------|-------|--------| | Stranger | 0-15 | -10% success, 50% effects | | Familiar | 41-60 | +10% success, 100% effects | | Friend | 61-80 | +20% success, greetings | | Soulmate | 91-100 | +50% success, psychic link |

Inventory (Bidirectional)

Objects stay in their home. Picking up = references, not file moves.

# Don picks up kitten:

# In don-hopkins.yml
inventory:
  - pub/cat-cave/kitten-myrcene.yml
  
# In kitten-myrcene.yml
location: characters/don-hopkins/inventory

# File didn't move. Location changed.

Reset: Snap objects back home: location = home.

Inventory Protocol (Objects vs Refs)

Items in inventory can be OBJECTS or REFS:

| Type | Weight | Bulk | What It Is | |------|--------|------|------------| | Object | Yes | Yes | The actual item (lamp, sword, lunchbox) | | Ref | No | No | Lightweight pointer to a prototype |

Refs are perfect for: catalogs, manuals, maps, guides — things you reference but don't physically carry.

inventory:
  # Full object
  - item: "Brass Lantern"
    type: object
    source: start/lamp.yml
    weight: 2
    fuel: 100
    
  # Lightweight ref
  - item: "ACME Catalog"
    type: ref
    prototype: street/lane-neverending/w1/acme-catalog.yml
    annotations: ["circled portable hole", "margin notes on physics"]

Dispenser Protocol

Some objects dispense refs (like the ACME Catalog Dispenser):

  1. TEAR OFF / TAKE at dispenser
  2. Receive REF in inventory (weight: 0)
  3. REF points to prototype for full content
  4. REF can accumulate instance-specific data (annotations, condition)

Drop Protocol

When dropping a ref in a room:

  1. Remove from inventory
  2. Create pointer file in room directory: [item-name].yml
  3. Pointer contains: prototype path, dropped_by, condition, annotations
  4. Item now lives in that room (can be picked up again)
# kitchen/acme-catalog.yml — dropped instance
object:
  name: "ACME Catalog"
  type: instance
  prototype: ../street/lane-neverending/w1/acme-catalog.yml
  origin: "Torn from dispenser at 4 Lane Neverending"
  dropped_by: "don-hopkins"
  annotations: ["DO NOT ORDER Rocket Skates", "circled portable hole"]

Capacity

inventory_capacity:
  max_weight: 45    # Varies by character
  max_bulk: 10
  refs_free: true   # Refs don't count!

Dispensers (Full Objects)

Some objects clone full objects on pickup. Original stays, you get instance.

# pub/cookie-jar.yml
object:
  id: cookie-jar
  dispenser: true
  instance_template: cookie

When picked up:

  1. Original stays
  2. Instance created: characters/don-hopkins/cookie-1.yml
  3. Instance inherits from prototype

Ephemeral vs Persistent

| Type | File? | Use For | |------|-------|---------| | Ephemeral | No | Quick transaction, one-line dialog | | Persistent | Yes | Ongoing negotiation, relationship state |

Rule: Will this matter in 5 minutes? No → ephemeral. Yes → persistent.

Stats

Two systems:

| System | Scale | Origin | |--------|-------|--------| | Sims Traits | 0-10 | The Sims 1 | | Mind Mirror | 0-7 | Timothy Leary |

Sims Traits

  • Neat — Sloppy ↔ Organized
  • Outgoing — Shy ↔ Social
  • Active — Lazy ↔ Energetic
  • Playful — Serious ↔ Fun-loving
  • Nice — Grouchy ↔ Kind

Distribution: Original Sims used 25 points across 5 traits. Good guideline.

Commands

| Command | Effect | |---------|--------| | LOOK AT [char] | Description, visible state | | TALK TO [char] | Conversation based on relationship | | HELLO [char] | Initiate social interaction | | GOODBYE [char] | End interaction, dismiss ephemeral | | EXAMINE [char] | Deeper observation |

External Homes

Characters can live in other repositories:

player:
  home: github:donhopkins/characters/don.yml
  location: pub/

Code Locations

Characters can be "at" a specific line in a file:

character:
  name: schema-expert
  home: characters/experts/schema-expert/
  location: "@central/apps/insights/pyleela/brain/Schema.py:142"
  # Currently examining line 142 of Schema.py

Location path syntax for code:

  • @repo/path/to/file.py — at a file
  • @repo/path/to/file.py:42 — at specific line
  • @repo/path/to/file.py:42-67 — examining line range
  • @repo/path/dir/ — in a directory (room)
> where is schema-expert?
schema-expert is at @central/apps/insights/pyleela/brain/Schema.py:142
examining the createSyntheticItemIfNeeded method

See room/ for directories as rooms and files as objects.

Party-Based Code Review

Form parties of expert characters to explore code together:

> summon drescher-expert, devops-expert, security-auditor
Party formed: [drescher-expert, devops-expert, security-auditor]

> party: review @central/tools/edgebox/scripts/ingest.py
drescher-expert: "The claim_task function is a schema pattern..."
devops-expert: "The PostgreSQL SKIP LOCKED is elegant..."
security-auditor: "I see proper parameter binding, good..."

> party: focus on lines 280-350
[Multi-perspective analysis of the code section]

Party Navigation:

> go to @central/apps/insights/pyleela/brain/
> enter Schema.py
> look at lines 140-180
> search for "synthetic"
> follow import ExtendedContext
> back
> party: gather here

Each party member brings their expertise. The LLM simulates all perspectives in a single call (see speed-of-light/).

Inner Voice (YAML Jazz)

Comments ARE the character's thoughts:

needs:
  hunger: 3
  # I could eat. But I'm comfortable here.
  # The kittens are asleep on my lap.

Motivation as Declared, Not Felt

Important distinction: When CHARACTER.yml specifies motivations, goals, or needs, these are declarative descriptions — they tell the LLM how to roleplay this character.

The LLM does not genuinely want to achieve these goals. It performs wanting them.

motivations:
  - protect_the_kittens     # Declared, not felt
  - find_good_food          # The LLM roleplays caring about this
  - explore_new_places      # No intrinsic drive — just character data

Why this matters:

  • No genuine agency — the character is a simulacrum
  • Roleplay all the way down (Shanahan)
  • Declared motivations are performed, not experienced
  • This is fine when acknowledged, problematic when mistaken for genuine will

See: representation-ethics/examples/aggregate-patterns.yml for the distinction between aggregate simulation (valid) and individual prediction (not valid).

K-line: MOTIVATION-ROLEPLAY

From the file to a first result

The download contains exactly the content displayed on this page. This copy may differ from the latest version in the source repository.

View the source and supporting files

This download contains SKILL.md only. Any scripts, references, templates and dependencies are not included. Get the required files from the source, preserving their directory structure, before continuing.

1. Download the file

Download SKILL.md

From the root of a test project, save the file as .skill-downloads/character-system-for-virtual-worlds-mm8o51wi/SKILL.md, or use the command below. This folder is for inspecting the skill before installation.

Command for macOS/Linux or WSL: requires a POSIX shell and curl. On Windows without WSL, use the download button and create the folder manually.

mkdir -p '.skill-downloads/character-system-for-virtual-worlds-mm8o51wi' && curl --fail --show-error --location 'https://skills-guides.com/api/skills/character-system-for-virtual-worlds-mm8o51wi/download' --output '.skill-downloads/character-system-for-virtual-worlds-mm8o51wi/SKILL.md.part' && mv '.skill-downloads/character-system-for-virtual-worlds-mm8o51wi/SKILL.md.part' '.skill-downloads/character-system-for-virtual-worlds-mm8o51wi/SKILL.md'

2. Check prerequisites

Read SKILL.md before using it. If it references scripts or external services, inspect them and prepare the required access in your test environment.

No recognized prerequisites section in this file. This does not mean it is self-contained: libraries, tools and access requirements may be mentioned elsewhere in the content or source repository.

The platforms on this page are catalog indications. The paths below follow tool documentation; they do not prove this skill has been run in those tools. No minimum tool version is confirmed for this listing.

3. Load the skill

After inspection, copy the complete folder into your project using one of the commands below, then open a new tool session. The command stops if a folder with the same name already exists: compare the files before replacing it.

Claude Code
test -f '.skill-downloads/character-system-for-virtual-worlds-mm8o51wi/SKILL.md' && test -s '.skill-downloads/character-system-for-virtual-worlds-mm8o51wi/SKILL.md' && mkdir -p '.claude/skills' && test ! -e '.claude/skills/character' && cp -R '.skill-downloads/character-system-for-virtual-worlds-mm8o51wi' '.claude/skills/character'

OpenSkills

OpenSkills must already be installed. The local install/read procedure is checked with OpenSkills 1.5.0, which requires Node.js ≥ 20.6.0. Catalog slugs are not resolved automatically.

Official OpenSkills installation
openskills install './.skill-downloads/character-system-for-virtual-worlds-mm8o51wi'

openskills read 'character-system-for-virtual-worlds-mm8o51wi'

Reading should display the installed file content and its base directory. It does not run the skill or install its dependencies.

For an agent that reads AGENTS.md, then sync the index. This command changes AGENTS.md: review the diff before using it.

openskills sync

Manual method or another tool: attach SKILL.md to a conversation, or open it in an agent that can read files. Include any required supporting resources. No universal folder is recognized by every tool.

4. Try a first task

Use a short, synthetic input: an API endpoint, a small document or an interface brief. In a new conversation, attach the file or give the agent its path, then adapt this request:

Read .skill-downloads/character-system-for-virtual-worlds-mm8o51wi/SKILL.md and apply its instructions to this example: [describe a test input]. Identify any missing files, dependencies or access. Produce the result requested by the skill without inventing data or running unreviewed scripts.

Expected result: output matching the skill instructions, or a precise list of missing prerequisites. A read confirmation alone does not validate a first use. If an external resource is unavailable, that path remains untested.

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