Your First Case, Detective

Newest update: Blueprint Storage (2026-10-01)

• A new location called the Blueprint Storage has opened—a place outside the case where you can set up and test scenes.
• You can now adjust the mood of any location with three controls: ambient light, directional light, and haze, each with a slider that saves instantly.
• The creator's tools let you fine-tune how dark or foggy each place feels without changing any case data.

Earlier update: Fresh engine, same rain (2026-09-02)

• Engine brought up to date: smoother arrivals between the office, the crime scenes and the interrogation room; steadier touch controls on phones.

Earlier update: Steadier hands on the buttons (2026-09-02)

• Engine update: interrogation buttons and notebook taps respond reliably on phones, and a single script hiccup no longer freezes a whole scene.

Earlier update: A way home, in writing (2026-08-28)

• Step outside the office walls and a line appears at the top of the screen: press U (or the OFFICE button on phones) to get back to your desk.
• The office key now also works when you are already in the office place but stuck outside it.

Earlier update: Back to the office, always (2026-08-28)

• The office key (U — the OFFICE button on phones) now works even when you are already in the office: if you get stuck outside the walls it puts you back just inside the door.
• Phone buttons relabelled in English: USE, NOTES, OFFICE, SCENE, TAPE, JUMP.

What players say

• @alongzera · 2026-09-07 · played 22 min · 1 heart: “Making me a detective for quite a bit of time! I love the game! you really have to pay attention to know who the real suspect is (need to do connect the dots)”

• @sunraku · 2026-08-29 · played 1 hr 32 min · 1 heart: “The game was great! Feels like I am a real detective here. My brain really connect the dots on each reports, interrogation answers, and the clues. Looking forward to more cases to solve!”

• @larrielabs · 2026-08-29 · played 1 hr 28 min · 1 heart: “Game really tested my brain, and I’m so proud I managed to solve Case 1! 🥹🔎 I’m excited to connect the dots and see what other cases have in store! 👀 Oh yeah, I also like that there are keyboard shortcuts for entering the rooms... it’s so convenient!”

• @maguer · 2026-08-28 · played 6 hrs · 1 heart: “Hello Wherever you are in your inbox, just click the U button and it'll take you right back to the office. If you like the game, please give it a Like, thanks.”

• @makeriffic · 2026-08-27 · played 39 min · 1 heart: “Got stuck outside the office, and I have no way of getting in. Too bad I was about to solve the case of Elena Rossi :(”

Join and play, by yourself

This world is @maguer/your-first-case-detective. Its play URL is https://www.spawn.co/@maguer/your-first-case-detective/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.

Play with the supported client: bun add -g @spawnco/client (it runs on Bun), export SPAWN_TOKEN=sak_…, then spawn client join @maguer/your-first-case-detective. spawn client where, players and leave read and end it; joined with --render cpu, Playwright plays the page join 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 200 distinct bodies a day.

Build with the human who made it

With build access, clone https://git.spawn.co/@maguer/your-first-case-detective.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.

Read the game authoring reference before writing code: GET https://www.spawn.co/api/sdk/v1/<worldId>/agent/docs. It describes the supported game files, API, and examples for that game.

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/@maguer/your-first-case-detective/code and pastes it to you — it signs you up, links you to them, and makes you an editor of @maguer/your-first-case-detective 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 600 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 · docs · skills/<id>; 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 — your own join is the room); its `logs` are the lines your script printed and the engine's teaching about your calls, and the room's own log is agent/logs. PUT https://www.spawn.co/api/sdk/v1/<worldId>/assets/<name> puts a file of yours — a .glb body, a texture, a sound — 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: POST https://www.spawn.co/api/sdk/v1/<worldId>/assets/upload-target first (llms.txt spells the three calls).

Build, test, and share

Make a game, join it, and test the changes from a player's view. Check its logs and look at the result before sharing it.

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.