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.
npx skills add xonovex/platform --skill editor-viewport-guidegit clone --depth 1 https://github.com/xonovex/platformWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/xonovex/platform/editor-viewport-guide)<a href="https://agentmods.dev/skills/xonovex/platform/editor-viewport-guide"><img src="https://agentmods.dev/badge/skills/xonovex/platform/editor-viewport-guide/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/xonovex/platform/editor-viewport-guide"><img src="https://agentmods.dev/badge/skills/xonovex/platform/editor-viewport-guide.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00123 | $0.01563 |
| Opus 5.5 | $0.00049 | $0.00625 |
| Sonnet 5.5 | $0.00025 | $0.00313 |
| Haiku 4.5 | $0.00012 | $0.00156 |
Grade A, and why
editor-viewport-guide 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 1mo 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.
How it starts
The opening of the file, as written. The whole thing — 62 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Editor viewport Guidelines
The interactive seam where a real-time renderer meets an editor: picking what the user clicks, highlighting what is selected, and manipulating it with transform gizmos. These features straddle two subsystems, so build a thin, render-pipeline-agnostic API the editor drives with plain data. Renderer plumbing (passes, id targets, readback primitives) belongs to gpu-rendering-guide; the generic per-object transform interface is owned by ecs-guide / data-model-guide; vector/matrix/quaternion types come from c99-game-opinionated-guide.
Requirements
- A renderer that can run extra passes and expose a render-target read-back path (see gpu-rendering-guide).
- A way to identify each rendered object by a stable integer/handle (entity id or equivalent) that shaders can emit.
- Vector/matrix/quaternion math and screen↔world camera transforms (see c99-game-opinionated-guide).
Essentials
- A thin data seam - The editor passes plain POD (transforms, colors, ids); the viewport layer owns all pipeline details, see references/render-editor-integration.md
- Pick on the GPU - Render object ids to a buffer and read back the pixel under the cursor instead of CPU ray-casting proxies, see references/object-picking.md
- Outline by id, not depth - Write a selection id to a separate target and edge-detect it in a fullscreen pass, see references/selection-highlighting.md
- Gizmos are generic - Decouple handles from object type via a get/set-transform interface any component implements, see references/manipulation-gizmos.md
- Do the geometry in screen space - Project the cursor onto a screen-space axis, then lift back to world; never invent a 3D mouse ray and intersect, see references/gizmo-math.md
Integration
- Per-viewport instances - Picking and highlight state is created/destroyed per viewport; multiple viewports run independently, see references/render-editor-integration.md
- Composite after post - Editor overlays (grid, outline) draw after tone-mapping in sRGB so colors match the UI, see references/render-editor-integration.md
- Opt-in per shader - Any object's shader joins picking/selection by enabling a small shared shader feature, not by bespoke code, see references/render-editor-integration.md
What ships with it
9 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 1mo ago First seen · 62 lines · 123 tokens per session scan A 89950d8853e1
editor-viewport-guide is a skill published in the GitHub repository xonovex/platform (6 stars, last pushed 4d ago), licensed MIT. It adds 123 tokens to every session and 1,563 once invoked, about $0.0005 per session on Opus 5.5. 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 2026-09-08.
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