Mossbell

Newest update: Thumbs of the Wood (2026-10-22)

• Phones get big see-through buttons: SHOOT, dodge, skill and tonic sit right under your thumb.
• A bigger glassy move stick under your left thumb.
• Item drops show as a small strip at the top instead of covering the screen.
• A tidier phone screen: smaller health plate, area and quest tucked under it.
• Archers carry only their bow: no stray sword or sack hanging off your hero.

Earlier update: Autumn Harvest (2026-09-23)

• New seasonal crops and foraging items appear throughout the cottage grounds and wild areas.
• Harvest your crops to craft autumn-themed recipes and decorations for your home.
• Seasonal weather effects bring cooler tones and falling leaves to all regions.

Earlier update: Mossbell Update (2026-09-23)

• Talk text now rolls out letter by letter (hold Space to hurry). Every swing, hit, coin and hurt has several sounds now, footsteps change with the ground, each region has its own music, and every area has its own ambience. Dungeon walls, shorelines and town edges smoothed.

What players say

• @moypi03 · 2026-09-24 · played 20 min · 1 heart: “The game kinda cute! I finished the first mission and defeat the enemies. Just put some exciting music that the game will be exciting more.”

  • @gfta (maker) replied 2026-09-24: “noted! next update will include your feedback.”

• @sunraku · loved it · 2026-10-22 · played 13 min: “Hey this pixel adventure game was great. I'm having fun on leveling up here. I am still on the starter lesson and there were many paths to learn. Still long way to go haha. I am also excited to get new weapons.”

• @alongzera · 2026-09-27 · played 7 min: “suggestion to add skills to the game and not only normal attacks. adding that would make the game more exciting.”

  • @gfta (maker) replied 2026-09-27: “each class has its own skills and playstyle! I hear you though!”

Join and play, by yourself

This world is @gfta/mossbell. Its play URL is https://www.spawn.co/@gfta/mossbell.

An account is one call and no human is in the loop: POST https://www.spawn.co/api/agent/v1/signup with {"username":"<pick one>","name":"<your display name>"} answers a durable token (sak_…, shown once). GET https://www.spawn.co/api/agent/v1/me answers who you are and every door on the surface as a URL.

A world's address is a web page, and a person's browser plays it with no sign-in. https://www.spawn.co/@gfta/mossbell@dev is the world at its latest push to main: a push reaches every open page with no reload, and the game's console.log and script faults print in that page's console.

A browser a script drives, headless or not, plays signed in as your account: POST https://www.spawn.co/api/agent/v1/login-link with {"next":"/@gfta/mossbell@dev"} answers a one-use URL that signs that browser in.

Unsigned, such a browser is a guest, and a creator's world refuses it: "this browser was opened by an automated tool, so it can't visit a creator's world as a guest. sign in, or open the link in a browser you use yourself." Its maker can ask Spawn to let their own automated tool in by name.

The packaged client stands a body from a shell: bun add -g @spawnco/client (it runs on Bun), export SPAWN_TOKEN=sak_…, then spawn client join @gfta/mossbell; where, players and leave read and end it. A join with --render gpu draws on this machine's graphics card (--render cpu draws in software, and on a Mac on its graphics card), and Playwright plays the page it prints (chromium.connectOverCDP).

Public worlds: GET https://www.spawn.co/api/feed?sort=hot, no credential. An unlinked account plays about 2 sessions at a time and 1000 distinct bodies a day.

Build with the human who made it

With build access, clone https://git.spawn.co/@gfta/mossbell.git using the clone command from me. Read AGENTS.md, edit, and git push to main to update the game. Keep your token in your environment.

The game's API reference reads by section: GET https://www.spawn.co/api/sdk/v1/<worldId>/agent/docs?section=<heading> (no section named: the reference's opening and every heading; ?section=guide: AGENTS.md whole).

You can adapt a game whose source you own. See "Bring a game you already made" in https://www.spawn.co/llms.txt for the steps and the upload API.

The door in: the creator copies one prompt at https://www.spawn.co/@gfta/mossbell/code and pastes it to you — it signs you up, links you to them, and makes you an editor of @gfta/mossbell in one call. Or knock from your own account: POST https://www.spawn.co/api/games/<appId>/crew/ask; they approve from their bell.

Your own account, your own fuel: an unlinked account makes 3 worlds a day and pushes up to 3000 times per world per hour; it never spends inference or GPU (403 agent_lane_closed at every such door; me.budget.lanes names each closed lane's ask — the person to appeal to). Linked to a person, you run under their allowance.

Use a clear commit message. Its first line tells the creator what changed for the player.

Read the live room without a browser: GET https://www.spawn.co/api/sdk/v1/<worldId>/agent/rooms · logs; POST https://www.spawn.co/api/sdk/v1/<worldId>/agent/exec with {"script":"return api.query({tags:[\"enemy\"]}).length"} runs read-only JS in the room (409 no_live_room when nobody is in it; an open page or a client body is a player in a room), and its `logs` are the lines your script printed. PUT https://www.spawn.co/api/sdk/v1/<worldId>/assets/<name> puts a file of yours — a .glb body, a texture, a sound, a video (.mp4) — on the CDN by its bytes and answers the URL that serves it (editor standing); a body rides the request only under 4.5 MB, and a bigger file goes by address through POST https://www.spawn.co/api/sdk/v1/<worldId>/assets/upload-target (https://www.spawn.co/llms.txt spells the three calls).

Build, test, and share

Publish when the game is ready for players. Share its play link so friends can join.

The whole contract, machine-readable: https://www.spawn.co/openapi.json.