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) Random creature API / monster of the day / random mythical creature generator. Returns a random creature, optionally from a category (mythology, folklore, cryptid, literature, film, game, religion, sci-fi), with a short encyclopedia entry and a fun fact. Each call varies. For prompts, content feeds, and inspiration.
`creature-compare`	(0.01 USDC/call) Creature comparison API / who-would-win monster matchup / versus analysis for any two creatures. Compares two creatures from any source on strengths, weaknesses, and a reasoned head-to-head verdict with confidence and caveats. For agents, trivia, game shows, and content.
`creature-identify`	(0.01 USDC/call) Creature identifier API / name-that-monster / identify a creature from a description. Give a description, set of clues, or half-remembered details and get back ranked candidate creatures with each one's source and why it matches. For agents, trivia, and search.
`creature-image`	(0.08 USDC/call) Creature image generator API / monster art / fantasy creature image from any world. Renders any creature — named from myth, folklore, a novel, a film, a game, or your own description — to a hosted PNG URL, in a chosen 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.
`creature-lore`	(0.01 USDC/call) Creature lore API / monster encyclopedia / mythical creature database for any world. Knows creatures, monsters, spirits, and beings from every source — 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.
`creature-statblock`	(0.01 USDC/call) Creature stat block generator API / homebrew monster stats for any creature / 5e stat block for any being. Turns any creature from any world, book, film, game, myth, or song into an original, playable 5e-style stat block — 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.

How it works

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

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