matlab-read-documentation

# Use MathWorks Documentation

Systematic methodology for reading live MathWorks documentation. Provides a repeatable four-pass strategy (local catalog → `help` → user guide pages → reference pages) that turns documentation lookup into a predictable, efficient operation. Uses MATLAB's `webread` via MCP to fetch pages, with helper scripts that handle URL discovery, HTML parsing, and content extraction.

## When to Use

- You are answering a "How do I..." question related to MathWorks products and workflows
- You guessed a URL and got 404 — use this skill to discover the correct URL from the index
- You need to find which functions exist for a product or workflow — start with the local function catalog
- You need to verify a function's syntax, arguments, or deprecation status from the authoritative source
- You want to check MathWorks best practices for a specific workflow
- Training-data knowledge is uncertain or potentially out of date for a release-specific API
- The user asks what MathWorks recommends for a specific topic
- You want a systematic approach that finds the RIGHT page (not just A page) in minimal tool calls

## When NOT to Use

- The local `help` command is sufficient — prefer `help function_name` for API syntax; it's faster and always correct for the installed version
- The question is about general MATLAB programming patterns, not product-specific workflows
- You already have the authoritative answer from local `help` or a successfully fetched page

## Fast Paths

Not every task needs the full four-pass strategy. Match the task to the shortest path:

| Task                                 | Fast Path                                                                                                                      | Skip                               |
| ------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------ | ---------------------------------- |
| Release notes / what's new           | Fetch `https://www.mathworks.com/help/{product}/release-notes.md` directly via `webread`, then extract the `## R20XXx` section | Steps 0-2 — no script needed       |
| Known standalone function, need ref page | Use a URL from a prior `extract_page_slugs` call, or construct `baseUrl + "ref/{name}.html"` for simple standalone functions | Steps 0-2 — but URL must come from a verified source, not guessed |
| Know the product, need function list | `get_local_function_list(product)`                                                                                             | Steps 1-4 — no web needed          |
| Unfamiliar API, no idea what exists  | Full four-pass strategy                                                                                                        | Nothing — use all steps            |

### Release notes

Release notes are available as clean markdown at `https://www.mathworks.com/help/{product}/release-notes.md`. Fetch this URL with `webread`, then extract the section between `## R20XXx` and the next `## R` header. No HTML parsing needed. Common product slugs: `matlab`, `simulink`, `ecoder`, `rtw`, `stateflow`, `fixedpoint`, `hdlcoder`.

## Help Center Page Hierarchy

- **Product landing page** — Lists top-level categories with short descriptions. Use to discover section slugs.
- **Intermediate category page** — Links to subcategories with one-line descriptions. No leaf content. Drill deeper.
- **Lowest-level category page** — Contains reference groups (functions, blocks, apps) then links to related topics and examples.
- **Topic pages** (`ug/` or product-specific path) — Conceptual or task-based content explaining how to use a feature.
- **Example pages** — Standalone worked examples with supporting files. May include live scripts, data files, or models.
- **Reference pages** (`ref/` or `slref/`) — Function, block, object, or property reference. Multiple subtypes: function ref, object ref, property list, block ref, app ref.
- **Getting started pages** (`gs/`) — Introductory tutorials for new users of a product.
- **Sequential topics** (STEP 1, 2, 3) indicate a workflow with an intended order.

## Choosing What to Fetch

MathWorks doc has two content layers that serve different purposes:

- **Guide pages** (user guide topics, typically under `ug/`) — Show *which* functions to call and in *what order*. Workflow-oriented. Best for learning a new API or deciding an approach. Note: not all products use `ug/` — some (Simulink, Statistics and Machine Learning) use different subdirectory structures. Always discover via the section index.
- **`ref/` pages** (function/object reference) — Show *exactly how* to call each function: full syntax, argument types, name-value pairs, valid enum values, return types, per-argument examples. Best when you know the function but need its exact signature. Some products use product-specific variants (e.g., Simulink uses `slref/`).

**You typically need both.** The `ug/` page tells you the recipe; the `ref/` page tells you the ingredient specifications. Skipping `ref/` means guessing at property names and argument values — which frequently fails because MathWorks APIs use domain-specific names that aren't intuitive (e.g., `"ArxmlFilePackaging"` not `"FilePackaging"`, `"StopTime"` not `"SimulationDuration"`).

### Page value signals (product-independent)

| Signal | Likely high value | Likely low value |
|---|---|---|
| Slug contains `programmatically`, `program-`, or `command-line` | Yes — always programmatic | — |
| Slug contains `property-map-functions` | Yes — API workflow | — |
| Slug contains `explorer`, `interactively`, `using-...editor` | — | Yes — GUI-only |
| Page type is `ref/` with object or function name | Yes — exact signatures | — |
| Page is very large (>30K) with product that has GUI+programmatic paths | — | Suspect GUI — measure before reading |
| Page under ~1500 chars between `Main Content` and footer | — | Likel