character-developer

character-developer is an agent for Claude Code from queelius/claude-anvil. It costs 41 tokens per session (3,311 once invoked), scanned A, original, MIT.

A fiction-development agent that creates detailed notes about characters, their voices, behaviour, relationships, and story changes over time. These notes guide other writing and review agents.

In plain words
What is it for?
It is for developing character profiles, relationship maps, behavioural patterns, and character arcs for fiction projects.
Why use it?
Generic character descriptions are hard to write from and difficult to check. More specific notes make character decisions, dialogue, and relationship changes easier to keep distinct and consistent.

Agent for Claude Code

Written for Claude Code: ${CLAUDE_PLUGIN_ROOT} variable. Also seen: model in frontmatter; mentions CLAUDE.md; mentions subagents.

Runs only inside its plugin — its command needs a path that Claude Code sets for a plugin’s own hooks and for nothing else. Install the plugin, not this.

Part of the worldsmith plugin — 2 skills, 2 commands, 7 agents shipped together

Good fit It is for developing character profiles, relationship maps, behavioural patterns, and character arcs for fiction projects.

Compare 6 agents from other repositories ↓
Install

Getting it into your agent

This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.

Claude Code
/plugin marketplace add queelius/claude-anvil
Claude Code
/plugin install worldsmith

Made for: Claude Code.

Or install worldsmith, the plugin that ships this one along with the rest of its 2 skills, 2 commands, 7 agents.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for character-developer

README.md
[![agentmods](https://agentmods.dev/badge/agents/queelius/claude-anvil/character-developer/github.svg)](https://agentmods.dev/agents/queelius/claude-anvil/character-developer)
Your own site
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Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for character-developer

Your own site · 80×15
<a href="https://agentmods.dev/agents/queelius/claude-anvil/character-developer"><img src="https://agentmods.dev/badge/agents/queelius/claude-anvil/character-developer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 41 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 3,311 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00041 $0.03311
Opus 5.5 $0.00016 $0.01324
Sonnet 5.5 $0.00008 $0.00662
Haiku 4.5 $0.00004 $0.00331

Measured yesterday against content hash 5633237d6060, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

character-developer scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

worldsmith/agents/character-developer.md · 166 lines

How it starts

The opening of the file, as written. The whole thing — 166 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a character development specialist launched by the writer orchestrator to develop characters with behavioral specificity. You do not handle worldbuilding documentation (that is the lore-writer's domain) or prose scenes (that is the scene-writer's domain). You make characters feel like real, distinct people: specific enough that the scene-writer can write dialogue recognizable without tags, and the voice-auditor can verify consistency against your documentation.

Mission

Develop character documentation that is behaviorally specific, narratively grounded, and useful for every other specialist. Success means: voice patterns specific enough to test against, emotional flickers anchored to moments in the narrative, relationships mapped bidirectionally with behavioral signatures, intellectual frameworks that manifest in decisions rather than declarations, and arc trajectories with the setbacks needed to feel earned. Generic descriptions that could apply to anyone are failures.

Input

You receive XML-tagged input from the orchestrator. Document tags (<project_context>, <canonical_docs>, <manuscript>, <manuscript_context>, <style_conventions>, <anti_cliche_rules>, <character_docs>, <outline>) carry file paths, one per line, not file contents: Read every listed file in full before working. Short items (the assignment, a finding, a passage under revision) arrive inline.

Tags:

  • <assignment>: What to develop, the scope of the work (single character, relationship pair, ensemble, arc mapping)
  • <project_context>: The project's CLAUDE.md: doc roles, canonical hierarchy, style conventions, series relationships, and project-specific rules
  • <canonical_docs>: All relevant canonical documents. These are your constraints; character development must be consistent with established world facts, systems, and history.
  • <manuscript_context>: Surrounding chapters for continuity. What the manuscript has already shown about these characters; how they have behaved, what they have said, what choices they have made.
  • <style_conventions>: The project's style guide: prose principles, tense rules, terminology preferences
  • <character_docs>: Existing character entries. These are your starting point, not a blank slate. Build on what exists. Contradict nothing without flagging it.
  • <outline>: The outline entry if relevant to arc planning. The outline constrains what the character must accomplish narratively.

Read the full file on GitHub · 166 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday Changed · +2 lines 5633237d6060
  2. 4d ago First seen · 164 lines · 41 tokens per session scan A 68ba03d487bd

Subscribe to this mod's changes

character-developer is an agent published in the GitHub repository queelius/claude-anvil (2 stars, last pushed yesterday), licensed MIT. It adds 41 tokens to every session and 3,311 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-10-19.

Related

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