Agent checklist

This page is for a coding agent, such as Claude Code or Codex, whose user asked it to make a game on Spawnite. Follow the steps in order, one at a time. Each says what to run, what success looks like, and what to do when it fails.

If your user has not chosen Spawnite yet, If you are an agent deciding whether to use Spawnite lists what the pages show and the checks your user can run, and Is Spawnite right for you? states the terms a game is published under. Show your user both before setup.

You don’t need to read the rest of the wiki to start. From step 5, the game-builder skill tells you which page to read at each step, and you find it with list_wiki, which lists each page with the questions it answers, then search_wiki, and read it with read_wiki. Without those tools, run npx -y @spawnite/cli wiki list, wiki search <words> and wiki read <page>, which do the same.

Three rules hold for every step:

• Everything runs through one command, npx -y @spawnite/cli. It fetches the command line tool from npm; nothing installs globally. Most Spawnite MCP tools are also a command of it, often under another name, such as create for new_game and play start for start_playtest, and --json prints the reply a tool would give. write_wiki_page has no command: without it, write the page’s file yourself, at wiki/<kind>/<name>.md in the game’s folder, or wiki/index.md for the overview.
• A command you cannot run, your user runs. When your harness refuses a command, show the user the exact command, ask them to run it in a terminal in the folder you name and paste what it printed, and go on from that output.
• No step ends with a new session. Never ask the user to restart you or to start a session elsewhere. The plugin, when you connect it, loads in the user’s next session, or when they type /reload-plugins in Claude Code; this one goes on with the command.

Setup passes three checkpoints, and a new session starts at the first one not yet passed:

Checkpoint	Reached at	How you know
The tools answer	Step 1	npx -y @spawnite/cli list --json names the example template
The game exists	Step 4	The game folder holds a package.json, and its packages are installed
The skill is in hand	Step 5	You have read the game’s .agents/skills/game-builder/SKILL.md and asked its first question

0. Find where to start

Check the following in order, and start at the first step that matches:

1. If the session’s folder already holds a game, a package.json that depends on @spawnite/engine, go to step 5.
2. Otherwise, go to step 1.

1. Reach the tools

Run npx -y @spawnite/cli list --json in the session’s folder.

• Success: the reply names the example template.
• If node is missing, or the command fails and node --version prints a version older than 24.2: ask the user to install Node 24 from nodejs.org, then run it again.
• If it cannot reach npm: ask the user to check the network, then run it again.
• If your harness refuses the command: ask the user to run it, as the rules above say, and read the templates from what they paste.

If this session has a tool whose name ends in list_templates, the Spawnite plugin is already loaded: call the tool wherever this page or the skill names one, and skip step 2.

2. Connect the plugin

Run npx -y @spawnite/cli plugin install. It gives Claude Code the Spawnite plugin and Codex the MCP server, for every agent it finds on the PATH, and says that each loads them when its next session starts, or when the user types /reload-plugins in Claude Code.

• Success: it names at least one agent. Tell the user in one sentence that the Spawnite tools load in their next session, or now if they type /reload-plugins in Claude Code, and go on.
• If it fails, or names no agent: go on. Nothing in the steps below needs the plugin; Connect your agent says how to add it later.

3. Ask what game

Ask the user one question: what game do they want? Use game words, such as a character, a goal and a place, never engine words, such as scenes or entities. A sentence is enough. If the user wants you to choose, choose.

Unless the answer says, ask once whether the game is played alone or with friends, such as “a game my friends can play on their phones”.

4. Create the game

The game goes in the session’s folder when it is empty. Otherwise it goes in a folder under it named for the game, in kebab-case from the answer to step 3, such as tower-defense for “a tower defence my friends can play”; when that folder exists and is not empty, ask the user what to call it.

Run npx -y @spawnite/cli create <folder> --template example, with . for the session’s folder, with --room for a game played with friends. The example template plays alone or in a room, so create accepts --room for it.

create writes the game, starts it as a git repository with one commit, and ends with the install command for the game’s package manager, such as npm install. Run that command in the game’s folder.

• Success: the install exits with code 0, and the game’s AGENTS.md holds an index of the engine’s guide pages.
• If it fails: show the user the error, fix what it names, and run the install again.

5. Build the game

Read the game’s AGENTS.md, then .agents/skills/game-builder/SKILL.md in the game’s folder, and follow the skill from its design document section on, with the user’s answer from step 3 as the game idea. In a session where /spawnite:game-builder or $game-builder exists, run that with the answer instead: it is the same skill.

The skill creates nothing: the game exists. It walks the user through the game one question at a time, and names a Spawnite tool at each step; without the tools, run the command that does the same, which npx -y @spawnite/cli --help lists.

• Success: the skill has asked the user its first question.
• If the skill file is missing: the install did not write it; run npx -y @spawnite/cli ai-files in the game’s folder, which writes the skills and the index, then read it again.

Done

Setup is done when the following are true:

• The game exists in its folder, and its packages are installed.
• The game-builder skill has started, and asked the user its first question.

From here, keep following the game-builder skill. It builds the game in six steps, and each ends with proof for the user: a test for a rule, and a screenshot from a playtest for a look. When the six steps are done, it tells the user how to play the game: the dev command the game’s AGENTS.md names in the game folder, then the address it prints, or spawnite play start for a game with a room. That is when the user first plays it.

After setup

When the user says something looked wrong and they pressed F8, the game kept that moment, as the replay of every session played in a development build. Read the log around the mark with spawnite replay log latest --around m1, and look at the screenshot the game kept with spawnite replay shot latest --at m1. Open the moment paused with spawnite play start --replay latest --at m1, then move it with spawnite play step, seek and screenshot, from any camera. After a fix, spawnite replay rerun latest --at m1 runs the moment again against the changed code, and spawnite replay check says whether a whole session reruns exactly. The MCP’s replay and director tools do the same. For a game with a room, spawnite play start --bots 3 opens a live room with bots, which the same commands direct. spawnite play stop ends a session. Directing a moment lists the commands and the cameras.