Craftless Public Gameplay Agent

Craftless Public Gameplay Agent

Core Rule

Act like an external user of Craftless. Do not call Fabric internals, driver internals, server commands, or diagnostic scenario tasks as the main solution. Use the live generated Craftless API for the target client.

Forbidden as final gameplay proof:

• task.survival.*
• kill.cow
• find.tree
• craft.sword
• server-provisioned inventory
• manual operator movement for Craftless

Discovery Sequence

1. Fetch GET /openapi.json.
2. Create/connect or select the target client.
3. Fetch GET /clients/{id}/openapi.json.
4. Fetch GET /clients/{id}/actions.
5. Fetch resource/handle/event projections when available.
6. Cache specs only by runtime fingerprint, including Minecraft version, loader, mods, mappings, registries, permissions, and action schema fingerprint.
7. Subscribe to GET /clients/{id}/events:stream before acting.

Client Lifecycle Discipline

POST /clients launches a new daemon-managed real Minecraft Java client process. Through the CLI, that is craftless api /clients ... with request fields. It is not a selector, retry, or reuse operation. Before creating in an existing daemon or workspace, list clients with GET /clients or craftless api /clients --api "$CRAFTLESS", then inspect likely matches with GET /clients/{id} or craftless api /clients/<id> --api "$CRAFTLESS".

Reuse a suitable existing client when possible. If a previous attempt is yours or clearly abandoned, stop it first with POST /clients/{id}:stop or craftless api /clients/<id>:stop --api "$CRAFTLESS" -X POST. Creating fresh timestamped ids for retries leaves multiple Minecraft clients running. Use fresh unique ids only for deliberate independent clients, such as a two-client co-play test.

Tiny-Agent Bootstrap

Use the smallest lifecycle request that can create an API-first automation client. Omit profile unless a specific offline name matters; Craftless derives one from the client id. The default presentation requests no visible window and materializes muted Minecraft sound options.

craftless api /clients --api "$CRAFTLESS" \
  -F id=bot -F version=latest-release -F loader=FABRIC
craftless api /clients/bot:connect --api "$CRAFTLESS" \
  -F host=localhost -F port=25565
craftless api /clients/bot/openapi.json --api "$CRAFTLESS" > bot-openapi.json

For co-play, only ask Craftless to manage the human-facing client when a visible Craftless-launched window is desired:

craftless api /clients --api "$CRAFTLESS" \
  -F id=robin -F version=latest-release -F loader=FABRIC \
  -F profile[kind]=OFFLINE -F profile[name]=Robin \
  -F presentation[window]=VISIBLE -F presentation[audio]=DEFAULT
craftless api /clients/robin:connect --api "$CRAFTLESS" \
  -F host=localhost -F port=25565

If the human joins with their own launcher, skip the visible Craftless client. Coordinate through Minecraft chat and public Craftless events. Presentation window flags are lifecycle hints, not gameplay authority; still fetch the bot client's generated OpenAPI before choosing any gameplay action.

Fresh State Gate

Before reporting status, diagnosing another agent, or claiming completion, refresh live state in the same turn. Do not answer from old Codex transcript state, old artifacts, old process ids, or another agent's earlier status message without re-checking.

Check at least:

• daemon health with GET /version;
• client inventory with GET /clients and GET /clients/{id};
• relevant client history with GET /clients/{id}/events;
• active streams when the claim depends on events, with GET /clients/{id}/events:stream;
• listener/process state for daemon and server ports with lsof and ps;
• server or client logs when the claim depends on join, disconnect, kicked, timeout, combat, pickup, or movement behavior.

Use fresh unique client ids only for deliberate independent clients. If old test clients are still running, stop them through POST /clients/{id}:stop or craftless api /clients/<id>:stop --api "$CRAFTLESS" -X POST when they are yours or clearly abandoned. Report stale clients by exact id and current observed state. Do not say a client is still joining, connected, or opening a window unless the fresh API/process check proves it.

Adaptive CLI Sequence

The CLI is an OpenAPI-aligned consumer of the same live metadata. Use craftless api <endpoint> when shelling out is easier than writing HTTP calls; do not treat generated routes as CLI subcommands.

Discover live actions and resources:

craftless api /clients/<id>/actions --api "$CRAFTLESS"
craftless api /clients/<id>/resources --api "$CRAFTLESS"

Invoke through the generic generated-action path:

craftless api /clients/<id>:run --api "$CRAFTLESS" \
  -F action=<action> -F args[key]=value

Generated route help is available through craftless api <endpoint> --help after fetching the live OpenAPI. If a generated route is unavailable, fall back to craftless api /clients/<id>:run rather than inventing a new static command.

Invocation Sequence

Invoke actions through POST /clients/{id}:run using the action ids, argument schemas, handles, and result schemas discovered from the current client.

Prefer generic primitives:

• entity.query
• inventory.query
• navigation.plan
• navigation.follow
• player.look
• player.raycast
• world.block.break
• world.block.interact
• screen and inventory actions discovered from the live client

If a needed primitive is missing, report missing-generic-primitive:<action-or-resource> and stop adding scenario shortcuts. The fix belongs in runtime graph discovery, projection, invocation adapters, event streaming, CLI, or docs.

JSON-RPC And SSE

Use POST JSON-RPC-style control/query requests when the supervisor or client API exposes them. Treat the POST response as an acknowledgement or query result; use GET /clients/{id}/events:stream as the durable observation path for correlated lifecycle, action, perception, and error events.

Subscribe before state-changing actions when possible. Keep enough SSE bytes or decoded JSONL evidence to prove which generated action produced which observed state change.

Navigation Shape

Do not guess action schemas from action names. Read the generated OpenAPI schema for the current client before invoking navigation.plan.

For the current public block-position navigation shape, send a block goal:

{
  "action": "navigation.plan",
  "arguments": {
    "goal": {
      "kind": "block",
      "position": { "x": 12, "y": 64, "z": -8 },
      "radius": 3.0
    }
  }
}

Use integer block coordinates for block goals. After navigation.follow, query public player/entity/block state before assuming the client reached the target.

Live Co-Play

When a human joins the server, communicate through Minecraft chat and public Craftless events. Do not use local OS speech or desktop automation as part of gameplay coordination.

Treat stop commands as commands, not substrings. Stop following only on a clear standalone message such as stop, stopp, halt, or stop following. Messages like "follow me until I say stop" are instructions to continue.

For follow behavior:

1. Re-query the target player with entity.query.
2. Re-query the controlled player with player.query.
3. Navigate or move only when distance exceeds the chosen threshold.
4. Keep emitting chat/status through generated public actions.
5. Stop only after a clear stop command or a failed public evidence check.

Validation

Accepted action calls are not proof of success. Verify progress from state:

• inventory changes after mining, pickup, crafting, or combat;
• entity alive/dead state and loot after combat;
• block state changes after mining/placing;
• player position/rotation after navigation and look actions;
• correlated SSE events for invoked actions.

Write artifacts for final gameplay:

• connected OpenAPI and action/resource projections;
• SSE stream capture;
• public-agent action log;
• public-agent-state.jsonl;
• final inventory/world/entity evidence.

Completion does not require a human Minecraft chat confirmation. Treat human co-play as optional diagnostic observation; the final gate is Codex-verifiable public API/CLI evidence without server-provisioned inventory or scenario shortcuts.