Did this copy code from the original dragon-beating repo?

No. The source repo has no license, so nothing was copied; this is an independent smaller build of the same planner-plus-bounded-controller split to run it with Hermes and reproduce the result.

Are the fast and cheap controller numbers trustworthy?

They are logged per run with probabilities, confidence, latency, and cost. The demo reached its goal in 4 actions at about 211 ms median, and the dragon reproduction finished faster at similar cost.

Why does the planner not act on every step?

It runs only at start, on targets or waypoint, after two failures, or every N actions, never per step, and emits JSON with objective, targets, and waypoint for the harness to enforce.

What happens when Jev keeps picking a useless move?

You change what gets offered. Mining stops once targets are met and wait appears only when nothing else is valid, which removed repeated useless picks in the next run.

What do I need to run it?

Node.js 18 or newer with no Java, since the Minecraft server is pure Node; a logged-in Hermes Agent for planning; and an OPENROUTER_API_KEY for the Jev controller, or CONTROLLER=hermes to let Hermes act too. Then npm install, RUN_ID=demo node harness.mjs, and node controller.mjs in a second terminal.

How did the Ender Dragon reproduction go?

Run end to end on Linux with the exact models, it beat the dragon in 7:45 against the original's 8:43, with 6 bed blasts, 0 deaths and $0.963 total ($0.010 Jev, $0.953 Astra). A substitute-model run took 12:37. Total spend across every run in the report was $1.96.

How is action validity decided?

The harness owns validity, not the model. The /options endpoint is the contract: the controller sees only executable, currently-useful moves and returns one key, and bad behaviour is fixed by changing what gets offered. After Jev kept choosing mine_dirt past the target and wait five times, mining stopped being offered once targets were met and wait only appears when nothing else is valid.

CommunityJev Practices & Patterns

Hermes And Jev Play Minecraft

Minecraft setup where Hermes plans at milestones, Jev picks one bounded harness action per step, and Mineflayer code owns validity and execution with no screenshots.

See highlights

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Stars: 10
Language: JavaScript
License: MIT
Published by: Community
Author: teknium1
Last verified: Oct 2026

teknium1/hermes-and-jev-play-minecraft

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Hermes Agent plans, Jev (TypeSafe) picks bounded actions, Mineflayer executes: Minecraft with no screenshots or keypresses from a model. Includes the reproduction of rmalde/minecraft-agent's Ender Dragon run.

Forks: 2
Last pushed: Updated Sep 2026

Repo stats from the GitHub API, cached Oct 2026.

About this project

Hermes Agent plans. Jev (TypeSafe's System-One model) picks one bounded action at a time. A Mineflayer harness decides which actions are valid and executes them. No screenshots, no keypresses, no generated code from any model.

Quoted from the project's README. Read the full README.

Tagscommunity awesomejev catalog-import

Works forJev for Classification Jev for Routing Jev for Tool calling

Used inJev for Software & DevTools

Languages: JavaScript

Highlights

Runs a pure-Node 1.16.5 server with one bot and an observe, options, act, and plan API.
Logs every plan and Jev decision with probabilities, confidence, cost, and latency.
Fixes bad behavior by changing offered options rather than prompt wording.
Supports Hermes-only control for watching and Jev control for fast runs.

Watch out

Needs Node, a logged-in Hermes install, and an OpenRouter key for the Jev controller; the original video was not reproduced with its macOS-only recorder. Copy reviewed against the repository README on 2026-10-04, not from running it.

Questions about this entry

Short answers drawn from the linked project or page.

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