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+# Skool — classroom course authoring (api2.skool.com)
+
+Create and fill classroom courses via Skool's private API. Auth is httpOnly cookies, so make
+credentialed `fetch(..., {credentials:"include"})` calls **from a logged-in Skool page context**
+(run them via `js(...)` / `Runtime.evaluate`). Must be a group admin.
+
+## IDs you need first
+
+Load any classroom page, then read the SSR blob:
+```js
+const pp = window.__NEXT_DATA__.props.pageProps;
+pp.currentGroup.id     // group_id
+pp.self.id             // user_id  (must be group-admin: pp.self.member.role)
+```
+
+## Content format: `[v2]` bare array (NOT doc-wrapped)
+
+A lesson body (`desc`) is the literal string `[v2]` followed by compact JSON of a **top-level ARRAY**
+of TipTap block nodes — NOT `{"type":"doc","content":[...]}`. If you have a doc-wrapped TipTap doc,
+unwrap it: `"[v2]" + JSON.stringify(doc.content)`. Supported nodes seen in the editor toolbar:
+paragraph, text (marks: bold, italic, strike, code, link), heading (H1–H4), bulletList/orderedList/
+listItem, blockquote, codeBlock, horizontalRule, hardBreak, image, video. Simplest reliable subset:
+paragraphs of text+marks, with `• `-prefixed lines for bullets.
+
+## The three calls
+
+**Create course (root):** `POST https://api2.skool.com/courses` → 200, returns the object incl. `id`.
+```json
+{"group_id":G,"user_id":U,"unit_type":"course","state":2,"is_afl_comp_eligible":false,
+ "metadata":{"title":"...","desc":"...","cover_image":"","privacy":0,"min_tier":0}}
+```
+`state:2` = published (state:1 = draft/unpublished). `privacy:0` = Open (all members).
+
+**Create module/lesson:** same `POST /courses` → 200, returns `id`. `unit_type` is `"module"` for
+BOTH section headers and lessons — the hierarchy is by `parent_id`:
+```json
+{"group_id":G,"user_id":U,"parent_id":<parent id>,"root_id":<course id>,
+ "unit_type":"module","state":2,"metadata":{"title":"...","resources":"[]"}}
+```
+- Lesson under the course: `parent_id = root_id = course id`. **This is the structure to use.**
+- **Display order = creation order.** There is no order field — create sequentially (await each).
+
+## Structure: use FLAT (course → lessons). 3-level does NOT render.
+
+You *can* POST a "module" whose `parent_id` is another module (course → section → lesson), and the
+API stores it 3 levels deep — but the classroom UI does **not** render it: the section shows as a
+flat row that opens its own (empty) content page, and its child lessons are invisible and unreachable
+to members. Every working Skool classroom course is 2-level. So: create all lessons directly under the
+course root, and encode module grouping in the title with a numeric prefix (`"1.1 …" … "6.5 …"`) plus
+list the module names in the course `desc`. Order the lessons by creating them in curriculum order.
+
+**Set lesson content:** `PUT https://api2.skool.com/courses/<id>` → **204**. Body is a FLAT 4-field
+object — NOT the metadata-wrapped create shape (sending the create shape returns 200 but silently
+no-ops):
+```json
+{"title":"...","desc":"[v2][...]","transcript":null,"video_id":""}
+```
+
+**Delete:** `DELETE /courses/<id>` → 200. Deleting a section cascades to its lessons.
+
+## Traps (field-tested)
+
+- **Title max = 50 chars.** Titles ≥ 51 fail the create with **HTTP 422** (silent in the UI). Keep
+  sidebar titles ≤ 49; put the full title as an H1 in the body if needed. 50 exactly passed, but stay
+  under — and remember a `"6.5 "` numeric prefix eats 4 chars, so cap the base title at ~45.
+- **Update needs the flat body.** The create body's `{...,metadata:{desc}}` shape does nothing on PUT.
+  Discover/confirm by editing one lesson in the UI and capturing the PUT (see below).
+- **Do NOT navigate the page while a fetch loop is running** — a reload kills the JS context and the
+  loop dies mid-way, leaving a partial course. Run the whole loop in one page context.
+- **Large payloads break the harness socket.** Injecting >~100KB in a single `Runtime.evaluate`, or
+  awaiting a 60+ call loop synchronously, times out the unix socket. Instead: push the payload in
+  chunks (per module), then FIRE the loop without `awaitPromise` while it writes progress to a global
+  (`window.__PROGRESS`), and POLL that global with short separate calls until `done`.
+- **`__NEXT_DATA__` is a stale SSR snapshot** — it does not reflect creates/deletes made this session.
+  For live tree state, `GET /courses/<course id>?group_id=G` → `{course, children:[{course, children}]}`.
+- **URL scheme:** course landing `/<group>/classroom/<course 8-char name slug>`; a specific lesson is
+  `?md=<lesson FULL id>` (the full 32-char id, NOT the short name). Wrong md → 404/Oops page.
+
+## Course-root update, reorder, and covers (field-tested 2026-07-16)
+
+**Update a course root** (rename, desc, cover): `PUT /courses/<id>` with a FLAT body — a different
+flat shape than the lesson PUT:
+```json
+{"title":"...","desc":"plain text","cover_image":"https://assets.skool.com/f/<group>/<hash>",
+ "privacy":0,"is_afl_comp_eligible":false,"min_tier":0}
+```
+- **TRAP: `GET /courses/<id>?group_id=G` does NOT return `coverImage` in metadata.** If you
+  read-modify-write from that GET and echo an empty `cover_image`, you silently WIPE the cover on
+  every course you touch. Get cover URLs from the classroom page SSR (`pageProps.allCourses[..]
+  .course.metadata.coverImage`) or a prior backup, and always echo them into the PUT.
+- Cover spec is **1460 × 752 px** (shown in the Edit course dialog). Assets survive metadata loss —
+  a wiped cover can be re-attached by URL without re-uploading.
+- Course title limit 50 chars applies to PUT too. Body `desc` here is plain text (course
+  description), NOT `[v2]` TipTap.
+
+**Reorder courses in the classroom grid:** `POST /courses/<id>/move2?dst=<index>` → 200, no body.
+`dst` is the absolute target index (0-based) in display order, not just adjacent-swap — one call can
+jump a course anywhere. Display order otherwise = creation order. The UI equivalent is the tile
+"⋯ → Move ←/→" menu.
+
+**`pageProps.allCourses` reflects live display order but caps at 30 entries** — courses beyond 30
+are silently absent (fetch them by id directly). `metadata.numModules` on a course root can drift
+(counts historical creates, not current children); count `children` from the GET tree instead.
+
+## Reference: capture any create/update call
+
+Enable `Network`, do the action once in the UI, drain events, filter `api2.skool.com` requests for
+`postData` + status. The "Add course" dialog's Published toggle + Open radio map to `state:2`,
+`privacy:0`. Editing a lesson and clicking SAVE emits the flat `PUT /courses/<id>`.