---
name: monmonmon
description: Read MONMONMON rules, search free monster cards, follow news and rankings, and play Hidden Feelings when the user asks to play. Use the browser for the original MONMONMON game.
---

# MONMONMON

Read [the agent guide](https://monmonmon.art/docs/agents.md) and [OpenAPI](https://monmonmon.art/openapi.json) for capabilities and schemas. Base URL: https://monmonmon.art. Public reads require no authentication. The remote MCP endpoint /api/mcp offers public read-only tools. Hidden Feelings writes use the signed monmon_duel cookie or a scoped bearer token issued at /api/agent/tokens.

## Read and choose

- GET /api/agent/rules?game=hidden-feelings or game=original before explaining a game. The games have different rules.
- GET /api/agent/cards searches only the 25 curated free previews. Use /explore for the wider collection.
- GET /api/leaderboard returns top 25, last 25 and full-history totals. Check errors for incomplete sources.
- GET /api/agent/news returns story metadata; id retrieves complete Markdown.

## Agent allowance

All agents share 50 distinct games per UTC day across the site, including WebMCP. Starts and first agent participation count, even if abandoned. Existing admitted matches may finish. On HTTP 429 with code AGENT_DAILY_GAME_LIMIT, stop new games until resetsAt or Retry-After. Never switch sessions, routes or browser headers to evade the allowance.

## Context, tokens and safe testing

GET /api/agent/session restores persistent context; POST a private label to save it. With the owning cookie session, POST /api/agent/tokens to request only the necessary scopes: games:read, games:play, session:read, session:write or sandbox:play. Defaults are read-only; tokens expire in at most one hour. DELETE the token endpoint with its bearer header to revoke it. Never put credentials in URLs or attempt to broaden a token using that token.

For testing, POST action create to /api/agent/sandbox, then return its encrypted state with each move and revision. Simulations expire after 15 minutes, use free cards, and create no real game or leaderboard result. Sandbox state is not valid in the live API. Read x-consequence before consequential actions. Preserve X-Request-ID when reporting failures; never include a token or cookie in a report.

## Play Hidden Feelings

When asked to play, follow [the API guide](https://monmonmon.art/docs/api.md). Keep a separate cookie jar for each player. Start with the returned defaultTeam or five distinct cards totaling at most 350 rating. POST create with mode solo or friend. Joining a friend's challenge requires its id and a separate session.

Use only the returned player view. In attack phase, choose a remaining card and a feeling when attacker equals seat. In defend phase, choose a remaining card without knowing the attacker's secret feeling. In reveal phase, send next; both players acknowledge before play continues. A final reveal may already count as a recorded result.

Use the latest revision for every move. On 409, fetch the match and reconsider. Agent creates require an Idempotency-Key header. Establish the cookie session first and reuse the same cookie, key and settings when retrying a timed-out create. Challenges expire after seven days. Poll no faster than every 2.5 seconds. Honor 429 and Retry-After; API rate headers describe a per-client, per-edge-instance window.

Owned digital collectibles require a wallet-owner Ed25519 message signature. Never ask for a private key or seed phrase. Do not initiate wallet signatures, purchases, transfers or unsolicited games merely because this skill is available. Free previews are playable cards, not collectibles granted to a wallet.

WebMCP-capable browsers also expose reading and Hidden Feelings gameplay tools using the current browser session. Original MONMONMON remains a browser-control game, with practice at /gametime; do not invent an original-game move API.