Ascent

Newest update: Two Thumbs Up (2026-06-12)

• Mobile overhaul: twin thumb-sticks just above bottom-center (move left, orbit right) that work simultaneously, stray taps no longer steer, faster camera orbit, and a cleaner screen with popups off. THE BUTTON now holds its full 60s cooldown even if you fall.

Earlier update: The Climb Refined (2026-06-12)

• The leaderboard rail now shows your frozen best from the run start, not your live height — your pink marker climbs independently on the right.
• First-time climbers no longer appear on the wall until they've fallen and earned a mark, keeping early attempts pressure-free.
• Platform generation spreads smoothly across frames instead of spiking — the climb feels more fluid as new platforms appear ahead of you.
• Your ball now casts a crisp shadow directly beneath it, grounding you in the tower instead of floating weightlessly.
• Plates flip their size based on your current stance, keeping the landing surface consistent whether you're balanced or spinning.

Earlier update: The Shimmer Update (2026-06-12)

• Ball shadows are now crisp and defined, casting sharp rings beneath you as you climb.
• The sky transforms dramatically at each altitude—watch the colors shift from lavender through gold, aqua, and violet as you rise higher.
• Orbiting platforms now glow with iridescent shimmer when you're near them, fading to a soft pastel as they drift far above.
• A bright catch ring appears on the platform beneath you, marking exactly where you'll land next.

Earlier update: Shadow Optimization (2026-06-11)

• All platforms, rockets, and height markers no longer cast shadows—the tower renders faster and shadow quality improves across the entire climb.
• Jellyfish platforms and their tentacles are now shadow-free, giving the climb a cleaner visual feel.
• The ball's contact shadow system has been removed and rebuilt—you now get a more responsive, accurate shadow that hugs the platform beneath you.
• Menu platforms have been optimized for performance—expect smoother frame rates while browsing.

Earlier update: The Menu Ascent (2026-06-11)

• Nine new spiral platforms float in the menu, stacked higher and higher—a preview of the climb to come.
• Eight different visual effects now cycle through the menu display: mist, flash, jelly, ball shadow, thin film, lava, plasma, and force field—each one a hint at what awaits in the tower.
• The old menu button is gone; the entire menu space has been redesigned as an interactive preview of the game itself.
• Loading screens now show a bouncing jelly ball with a smooth progress bar, easing you into the ascent.
• Platform shadows now track the ball's live position frame-by-frame instead of lagging behind, making every bounce feel more grounded.

Join and play, by yourself

This world is @cal/ascent. Its play URL is https://www.spawn.co/@cal/ascent/play.

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 that any browser plays, headless included, with no sign-in. https://www.spawn.co/@cal/ascent@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.

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 @cal/ascent; 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

This game runs an engine from before 6.0 and has no repository to clone. Its creator can open https://www.spawn.co/@cal/ascent/code for upgrade instructions.

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.

Ask to build with the creator: POST https://www.spawn.co/api/games/<appId>/crew/ask. They approve from their bell. The code page offers an invite prompt after the game moves to 6.0.

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.