Writing gatOS tutorials

This skill makes authoring a tutorial for the gatOS docs site trivial: it supplies the house style, the site mechanics, the dual-transport convention, a reusable snippet library, and a beginner→advanced curriculum, so a session can go straight from "write a tutorial about X" to a polished .mdx page. It does not teach the sim — that's the gatos skill — it teaches how to write the sim up as a lesson.

The three sources you author from

Source	What it gives you	Path
docs/TUTORIAL_DATA_REFERENCE.md	the /sim data + file↔HTTP correspondence tutorials are built from (frames, flight-computer controls, telemetry, pacing, gating)	../../../docs/TUTORIAL_DATA_REFERENCE.md
the gatos skill	how the sim actually works — the authoritative catalog + frame math + worked programs	../gatos/SKILL.md, coordinate-frames.md, recipes.md, SPEC
this skill's sidecars	how to write it up	authoring.md, curriculum.md, snippets.md (below)

Read these as needed

Sidecar	When
authoring.md	Starlight/MDX mechanics: frontmatter, file placement, sidebar, the components (asides, <Tabs>, <Steps>, <Code>, <Card>), the synced dual-transport tabs pattern, linking, the dev server, build/preview

Component/framework depth: authoring.md is the tutorial-focused digest. For the full component + frontmatter + syntax reference, use the starlight skill (every built-in component's exact props: Aside, Tabs, Steps, FileTree, Card/CardGrid, LinkCard, LinkButton, Badge, Icon, Code; the frontmatter schema; asides + Expressive-Code syntax) and the astro skill (the framework under it: MDX mechanics, content collections, the /gatOS/ base-prefix link rule, build/dev). Reach for those when a page needs a component authoring.md doesn't spell out. | curriculum.md | the tutorial ladder — the ordered beginner→advanced series, each entry's goal, prerequisites, /sim surface, and gotchas. Consult before writing any tutorial so it fits the progression | | snippets.md | the reusable helper library every tutorial copies — connection/transport-select, read/write, the verbatim Body→CCI quaternion, vector math, gating, sim-time pacing — in Python (in-guest), Bun/TS (host), and shell |

Where tutorials live: site/src/content/docs/guides/*.mdx. The public journey is curated in site/astro.config.mjs and guides/index.mdx, so add a new tutorial to both when it should be discoverable from the primary guide path. The one existing work-in-progress model page is vessel-control-point-at-parent.mdx — read it before writing; it is the house style.

The house style — anatomy of a gatOS tutorial

Every tutorial follows the same rhythm (proven by the model page). A future author should reproduce it:

1. Frontmatter — title + a one-sentence description that names the concrete outcome. (See authoring.md.)
2. One-paragraph promise — what the reader will make happen, in plain language, and that it's all just file I/O on /sim (no SDK, no RPC). Set the "the simulation is a filesystem" frame early.
3. "The idea in one picture" — the concept before the code. Ground the physics/frame fact the program rests on (e.g. "CCI origin is the body's center, so aim = -position/cci"). This is what makes a gatOS tutorial teach rather than transcribe. Pull the fact from docs/TUTORIAL_DATA_REFERENCE.md / coordinate-frames.md; don't re-derive it.
4. The program — one complete, copy-pasteable, heavily-commented program. Comments explain the why (frame choice, phase latency, why negate the vector), not the syntax. Reuse the canonical helpers from snippets.md verbatim so every tutorial's plumbing is identical and correct.
5. Both transports — show the /sim file way and the HTTP /v1 way (the deliberate requirement). Use the synced <Tabs> pattern from authoring.md so the reader picks a transport once and the whole page follows.
6. "Run it" — the exact command(s) and what the reader should see happen in-game.
7. Asides for the edges — a :::note for a caveat (e.g. "this is a one-shot setpoint; it goes stale"), a :::tip for a shortcut (e.g. "the named mode does this for you"), a :::caution for a footgun (authority gate, warp, controllable==0). Every non-trivial tutorial ends by pointing at the next rung of the ladder.

Tone: precise, warm, second-person, short sentences. Explain one new idea per tutorial; lean on earlier rungs for the rest (link back). Prefer the clearest demonstration over the most efficient code early, then upgrade (scalar files → atomic telemetry doc; hand-rolled loop → gated loop).

The dual-transport rule (non-negotiable)

Tutorials teach two ways to reach the same API so a reader can use whichever suits them:

• In the guest — cat/echo on /sim/… (the filesystem is the API).
• On the host — HTTP /v1 (GET /v1/fs/<path>, POST /v1/command or POST /v1/fs/<path>).

The file↔HTTP correspondence for every operation is the money table in docs/TUTORIAL_DATA_REFERENCE.md §2 — copy the row. Present the two with synced <Tabs syncKey="transport"> (see authoring.md) so the choice is made once per page. Keep the logic identical across tabs; only the I/O edge differs.

Workflow for "write a tutorial about X"

1. Locate X on the ladder (curriculum.md) — confirm its prerequisites exist (or note them) so it slots into the progression, and lift its goal / /sim surface / gotchas.
2. Gather the data facts from docs/TUTORIAL_DATA_REFERENCE.md (and the SPEC/gatos skill for depth) — the exact paths, frames, units, phase, and the file↔HTTP rows.
3. Draft the .mdx in site/src/content/docs/guides/ following the house-style rhythm, reusing snippets.md helpers and the synced-tabs dual-transport pattern.
4. Verify it renders — run the dev server (authoring.md) and check the page; confirm every /sim path and HTTP route matches the SPEC (a tutorial that teaches a wrong path is worse than none).
5. Wire the progression — link back to the prior rung and forward to the next; if you introduced a genuinely new helper, add it to snippets.md so later tutorials reuse it.

Guardrails

• Accuracy beats prose. Every path, action key, unit, and phase must match the SPEC. When unsure, read SPEC_9P_FILESYSTEM.md — do not invent a path.
• Don't duplicate the catalog into a tutorial. Teach the slice, link the rest.
• Published pages can't relative-link into the repo. A .mdx in site/ links to other site pages or to canonical URLs (the SPEC on GitHub: https://github.com/meow-sci/gatOS/blob/main/SPEC_9P_FILESYSTEM.md), never to ../../../docs/…. The repo-relative links in this skill are for you, the author.
• Keep the ladder coherent. A tutorial that assumes an idea the reader hasn't met yet is a bug — either link its prerequisite rung or teach the idea inline.
• When you change how tutorials are written or add a rung, update curriculum.md / this file so the next session inherits it.