zenith AGENTS.md

Repository instructions for Zenith, a Rust workspace whose separate packages handle geometry, parsing, text layout, rendering, and visual checks. They define each package's responsibility and allowed dependencies.

In plain words
What is it for?
Use them when adding or changing Zenith code, especially geometry, parsing, text shaping, raster rendering, scenes, or visual-quality checks.
Why use it?
They help contributors preserve the project's architecture, stable boundaries, and rules for how its Rust packages may depend on one another.

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/zenitheditor/zenith/agents-md
Clone the repo
git clone --depth 1 https://github.com/zenitheditor/zenith

Made for: Codex, OpenCode.

Per session 1,537 This file is loaded in full into every session.
When invoked 1,537 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 $0.01537 $0.01537
Opus 5 $0.00768 $0.00768
Sonnet 5 $0.00307 $0.00307
Haiku 4.5 $0.00154 $0.00154

Measured 2d ago against content hash 8924c8efb196, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

zenith 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 · 79 lines

How it starts

The opening of the file, as written. The whole thing — 79 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Repository Guidelines

This file is the source of truth for working in the Zenith repository — for human contributors and AI agents alike. Read it before making changes.

Project Structure & Module Organization

Zenith is a Rust workspace (edition = "2024"). Each crate owns one concern and exposes a stable contract; zenith-geometry depends on no other Zenith crate; zenith-core may depend only on pure zenith-geometry for path math (validation / fill queries).

  • zenith-core/ — KDL parser adapter, semantic AST, canonical formatter, tokens, validation, the full diagnostic set. May depend on pure zenith-geometry only among Zenith crates.
  • zenith-geometry/ — pure geometry (paths, contours, booleans). C-free; depends on no other Zenith crate; used by core, layout, scene, and tx.
  • zenith-layout/ — text shaping & font metrics (rustybuzz + ttf-parser); all third-party shaping types confined here.
  • zenith-raster/ — raster surface, blend modes, adjustments used by perception and render.
  • zenith-perception/ — visual QA / perception reports over geometry + raster.
  • zenith-scene/ — backend-neutral scene IR and compilation (geometry, text wrap, anchors, opacity/clip, text outlines).
  • zenith-render/ — CPU PNG backend (tiny-skia) and vector PDF backend; raster-time determinism rules.
  • zenith-tx/ — transaction op set, apply/dry-run engine, diffs, audit-record contract. Pure AST; no scene/layout dependency.
  • zenith-session/ — local doc identity (ULID), ephemeral session DAG, durable content-addressed version store. Never on the render path.
  • zenith-zpx/ — packaged design export (manifest + bake).
  • zenith-producers/ — higher-level produce/export helpers (SVG native, ZPX bake).
  • zenith-cli/ — the zenith binary (crate package name zenith-tool): command dispatch, clap, JSON/human output, MCP. src/main.rs is thin; logic lives in src/lib.rs and src/commands/.
  • examples/ — runnable .zen documents (keep them valid against the current parser).
  • assets/ — bundled fonts (assets/fonts/) and embedded library presets (assets/libraries/). Committed.
  • conformance/ — regenerable rendered proof of simulation scenarios. Gitignored; never stage it.
  • resource/, .agents/, .claude/, .codex/ — local planning/research/session scratch. Gitignored.

Read the full file on GitHub · 79 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 · 79 lines · 1,537 tokens per session scan A 8924c8efb196

Subscribe to this mod's changes

zenith AGENTS.md is an instructions file published in the GitHub repository zenitheditor/zenith (22 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 1,537 tokens to every session, about $0.0077 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.