mars AGENTS.md

A set of development instructions for Yazelix's Mars terminal, a command-line application derived from Rio. It describes project workflow, source-code boundaries, validation, and release practices.

In plain words
What is it for?
Use it when developing Mars features, planning changes with Beads, checking related terminal behavior, updating packaging or documentation, and recording validated changes.
Why use it?
It gives coding agents clear rules for changing Mars while keeping updates small and easier to merge with the upstream project. It also helps distinguish Mars-owned files from inherited code.

Instructions file for CodexOpenCode

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add instructions/yazelix/mars/agents-md
Clone the repo
git clone --depth 1 https://github.com/Yazelix/mars

Made for: Codex, OpenCode.

Per session 510 This file is loaded in full into every session.
When invoked 510 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00510 $0.00510
Opus 5 $0.00255 $0.00255
Sonnet 5 $0.00102 $0.00102
Haiku 4.5 $0.00051 $0.00051

Measured 2d ago against content hash fffdc75e0ab7, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

mars AGENTS.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

AGENTS.md · 53 lines

How it starts

The opening of the file, as written. The whole thing — 53 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Mars Agent Guide

Mars is a Rio-derived terminal fork maintained for Yazelix and agent-driven development. Keep changes small, measured, and easy to rebase against upstream Rio.

Workflow

  • Use br for Beads planning in this repository
  • Plan behavior work in Beads before editing Rio-owned source
  • Prefer additive Mars-owned files over broad Rio source rewrites
  • Keep each feature small, measurable, and easy to remove or upstream
  • Compare relevant Ghostty and WezTerm behavior before terminal-behavior edits
  • Search Rio issues and current upstream Rio commits before local Rio-owned source changes
  • Record Mars-owned code or runtime-behavior commits in docs/yazelix/change_scorecard.md
  • Preserve normal non-Nix packaging routes where practical, but avoid public support claims until each path is validated

Source Boundaries

  • Rio-owned source includes the inherited crates and frontend/backend terminal code
  • Mars-owned surfaces include pkgMars.nix, flake.nix, misc/mars.desktop, tools/mars_*, and docs/yazelix/*
  • Prefer package, wrapper, config, desktop, docs, and tool changes before renderer, PTY, parser, event-loop, or window changes
  • If a direct Rio-owned source edit is smaller than an abstraction, keep it direct and document why in the Bead or scorecard

Validation

Choose checks proportional to the touched surface:

  • README/docs only: git diff --check
  • GitHub workflow changes: actionlint .github/workflows/<file>.yml
  • Nix package or metadata changes: nix eval --json .#packages.x86_64-linux.mars.passthru.marsPackageMetadata --no-write-lock-file
  • Mars package changes: nix build .#mars --no-link --print-build-logs
  • Rust changes: cargo fmt -- --check --color always, cargo clippy --all-targets --all-features, and cargo test --features wgpu

Release Workflow

The release workflow runs for v*.*.* tags and manual dispatch only. Do not re-enable ordinary main push releases unless the GoReleaser Pro and Apple signing secret policy is decided and documented. The release-secrets evaluation is tracked by Bead yzt-c2d.

Read the full file on GitHub · 53 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 53 lines · 510 tokens per session scan A fffdc75e0ab7

Subscribe to this mod's changes

mars AGENTS.md is an instructions file published in the GitHub repository Yazelix/mars (23 stars, last pushed 3d ago), licensed MIT. It adds 510 tokens to every session, about $0.0026 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.