@agentutility/mcp-bestiary

A creature compendium for every world.

Creatures from myth, folklore, novels, films, games, and song. Pull a creature's lore, stat it for the table, run a head-to-head matchup, identify one from a description, or render its portrait — any being, any universe.

Pricing: pay-per-call in USDC on Base. No subscriptions, no API keys. See per-tool prices below.

Install — Claude Desktop

Edit ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):

{
  "mcpServers": {
    "agentutility-bestiary": {
      "command": "npx",
      "args": ["-y", "@agentutility/mcp-bestiary"],
      "env": { "X402_PRIVATE_KEY": "0xYOUR_PRIVATE_KEY_HEX" }
    }
  }
}

Restart Claude Desktop. 6 tools appear in the tool palette.

Install — Cursor

Add to .cursor/mcp.json:

{
  "mcpServers": {
    "agentutility-bestiary": {
      "command": "npx",
      "args": ["-y", "@agentutility/mcp-bestiary"],
      "env": { "X402_PRIVATE_KEY": "0x..." }
    }
  }
}

Funding

Send any amount of USDC on Base mainnet to the address derived from your X402_PRIVATE_KEY. The MCP server uses it to pay for tool calls automatically.

USDC on Base contract: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

Tools (6)

| Tool | Description | |---|---| | bestiary-random | (0.01 USDC/call) Returns a random creature with a short encyclopedia entry and a fun fact. Optionally pick from a category (mythology, folklore, cryptid, literature, film, game, religion, sci-fi). Each call varies. For prompts, content feeds, and inspiration. Use it as a random creature API, monster of the day, or random mythical creature generator. | | creature-compare | (0.01 USDC/call) Compares any two creatures head-to-head and reasons out who would win. Weighs strengths and weaknesses of creatures from any source and returns a reasoned verdict with confidence and caveats. For agents, trivia, game shows, and content. Use it as a creature comparison API, who-would-win monster matchup, or versus analysis tool. | | creature-identify | (0.01 USDC/call) Identifies a creature from a description, set of clues, or half-remembered details. Returns ranked candidate creatures with each one's source and why it matches. For agents, trivia, and search. Use it as a creature identifier API or name-that-monster tool. | | creature-image | (0.08 USDC/call) Renders any creature as an image and returns a hosted PNG URL. Name a creature from myth, folklore, a novel, a film, a game, or your own description, and pick an art style (fantasy-art, realistic, anime, oil-painting, ink-sketch, watercolor, pixel-art, comic-book). Pairs with the bestiary lookups: read the lore or stat block, then picture the monster. Text-to-image via Venice, output hosted on fal. Use it as a creature image generator API, monster art source, or fantasy creature image maker. | | creature-lore | (0.01 USDC/call) An encyclopedia of creatures, monsters, spirits, and beings from any world or source. Covers world mythology and folklore, religion, cryptozoology, novels, films, games, comics, and song. Given a creature name (and optional source to disambiguate), returns a structured encyclopedia entry: origin, category, physical description, abilities, weaknesses, behavior, habitat, cultural significance, notable appearances, and a danger level. Reference and commentary in the model's own words. Use it as a creature lore API, monster encyclopedia, or mythical creature database. | | creature-statblock | (0.01 USDC/call) Turns any creature from any world, book, film, game, myth, or song into an original, playable 5e-style stat block. Returns AC, HP, ability scores, challenge rating, traits, and actions as original game statistics (not a copied published block). Optionally target a challenge rating. Bridges the bestiary and rollforge clusters. Use it as a creature stat block generator API or a source of homebrew monster stats for any being. |

How it works

1. Agent calls a tool (e.g. bestiary-random).
2. MCP server POSTs to https://x402.agentutility.ai/bestiary-random.
3. The endpoint responds HTTP 402 with payment instructions.
4. The MCP server signs an EIP-3009 USDC transfer authorization with X402_PRIVATE_KEY and retries.
5. CDP facilitator settles on Base.
6. The endpoint returns the actual response.

The agent never sees the payment flow — it just gets the result.

Links

• Cluster overview: https://agentutility.ai/bestiary/
• All MCP packages: https://mcp.agentutility.ai/
• Source: https://github.com/rooz21/x402/tree/main/packages/mcp-bestiary

Version: 0.1.3 · License: MIT