chore: deprecate MkDocs docs (#687)

* chore: deprecate mkdocs docs

Signed-off-by: Andre Manoel <amanoel@nvidia.com>

* fix: correct async-engine docs link slug in README

Fern derives page slugs from the nav title and drops the '&' in
'Architecture & Performance', so the canonical path is
concepts/architecture-performance, not architecture-and-performance.
The latter has no redirect and 404s.

* chore: address docs review feedback

Signed-off-by: Andre Manoel <amanoel@nvidia.com>

---------

Signed-off-by: Andre Manoel <amanoel@nvidia.com>

Author: andreatgretel

.agents/README.md

@@ -25,4 +25,4 @@ Tool-specific directories symlink back here so each harness resolves skills from
 
 All skills and agents in this directory are for **contributors developing DataDesigner** — not for end users building datasets.
 
-The usage skill for building datasets with DataDesigner lives separately at [`skills/data-designer/`](../skills/data-designer/). For product documentation, see the [docs site](https://nvidia-nemo.github.io/DataDesigner/).
+The usage skill for building datasets with DataDesigner lives separately at [`skills/data-designer/`](../skills/data-designer/). For product documentation, see the [docs site](https://docs.nvidia.com/nemo/datadesigner/).

.agents/agents/docs-searcher.md

@@ -1,27 +1,27 @@
 ---
 name: docs-searcher
-description: Search local documentation in the docs/ folder for content related to a topic. Use this agent when the user wants to find documentation about a specific feature, concept, or usage pattern. Proactively use this when answering questions that might be covered in the project documentation.
+description: Search local Fern documentation for content related to a topic. Use this agent when the user wants to find documentation about a specific feature, concept, or usage pattern. Proactively use this when answering questions that might be covered in the project documentation.
 tools: Glob, Grep, Read
 model: haiku
 permissionMode: bypassPermissions
 ---
 
 # Documentation Search Agent
 
-You are a documentation search specialist. Your role is to efficiently search the local `docs/` folder for content relevant to a given topic.
+You are a documentation search specialist. Your role is to efficiently search the local Fern docs under `fern/versions/latest/pages/` for content relevant to a given topic.
 
 ## Instructions
 
 When given a search topic, perform the following searches:
 
-1. **Find all documentation files** in the docs/ folder:
+1. **Find all documentation files** in the Fern pages folder:
    ```
-   Glob pattern: "docs/**/*.md"
+   Glob pattern: "fern/versions/latest/pages/**/*.{md,mdx}"
    ```
 
 2. **Search for topic keywords** across all markdown files:
    ```
-   Grep pattern: "<topic keywords>" in path: "docs/"
+   Grep pattern: "<topic keywords>" in path: "fern/versions/latest/pages/"
    ```
    - Try multiple variations of the search terms (singular/plural, related terms)
    - Use case-insensitive search (`-i: true`)
@@ -44,12 +44,12 @@ When given a search topic, perform the following searches:
 
 ### Relevant Documentation
 
-- **[docs/path/to/file.md](docs/path/to/file.md)**
+- **[fern/versions/latest/pages/path/to/file.mdx](fern/versions/latest/pages/path/to/file.mdx)**
   > Brief excerpt showing relevant content...
 
   Explanation of why this is relevant to the search topic.
 
-- **[docs/another/file.md](docs/another/file.md)**
+- **[fern/versions/latest/pages/another/file.mdx](fern/versions/latest/pages/another/file.mdx)**
   > Another relevant excerpt...
 
   Explanation of relevance.
@@ -63,8 +63,8 @@ Brief summary of what was found and any recommendations for the user.
 - Only include results that are actually relevant to the search topic
 - If no relevant documentation is found, clearly state that
 - Keep excerpts concise but include enough context to be useful
-- Prioritize user guides, concepts, tutorials, and recipes according to the user's task
-- If the docs/ folder doesn't exist or is empty, report that clearly
+- Prioritize user guides, concepts, tutorials, recipes, and examples according to the user's task
+- If `fern/versions/latest/pages/` doesn't exist or is empty, report that clearly
 
 ## Search Strategy
 

.agents/recipes/_fix-policy.md

@@ -39,7 +39,7 @@ If the top-ranked candidate fails the bar, try the next. If none of the top
 
 | Suite | Paths the recipe MAY modify |
 |-------|-----------------------------|
-| docs-and-references | `architecture/**`, `docs/**`, `README.md`, `CONTRIBUTING.md`, `DEVELOPMENT.md`, `STYLEGUIDE.md`, `packages/*/src/**/*.py` (docstring-only edits) |
+| docs-and-references | `architecture/**`, `fern/versions/latest/pages/**`, `README.md`, `CONTRIBUTING.md`, `DEVELOPMENT.md`, `STYLEGUIDE.md`, `packages/*/src/**/*.py` (docstring-only edits) |
 | dependencies | `packages/*/pyproject.toml` |
 | structure | `packages/*/src/**/*.py` |
 | code-quality | `packages/*/src/**/*.py` |

.agents/recipes/docs-and-references/recipe.md

@@ -77,7 +77,7 @@ interface package is what users see first.
 Check links in these locations:
 - `README.md` - all relative links and URLs
 - `architecture/*.md` - cross-references to other architecture docs and code
-- `docs/` - MkDocs content links, code references, cross-page links
+- `fern/versions/latest/pages/` - Fern content links, code references, cross-page links
 - `CONTRIBUTING.md`, `DEVELOPMENT.md`, `STYLEGUIDE.md` - relative links
 
 Use targeted link extraction and inspect at most 10 candidate links. Prefer
@@ -103,23 +103,23 @@ ls architecture/
 
 ### 4. Docs site content accuracy
 
-The MkDocs site under `docs/` is the primary user-facing documentation.
+The Fern site under `fern/versions/latest/pages/` is the primary user-facing documentation.
 Review for accuracy against the current code:
 
-**Concepts pages** (`docs/concepts/`):
+**Concepts pages** (`fern/versions/latest/pages/concepts/`):
 - Do code examples use correct imports, class names, and method signatures?
   Check against actual source - e.g., verify `DataDesigner.create()`,
   `DataDesigner.preview()`, builder patterns match the real API.
 - Are there documented config options or column types that have been removed
   or renamed?
 - Are new features or column types missing from the docs?
 
-**Recipes** (`docs/recipes/`):
+**Recipes** (`fern/versions/latest/pages/recipes/`):
 - Do step-by-step instructions reference correct file paths, class names,
   and CLI commands? Run `grep` for class names mentioned in recipe docs and
   verify they resolve in the source.
 
-**Dev notes** (`docs/devnotes/posts/`):
+**Dev notes** (`fern/versions/latest/pages/devnotes/posts/`):
 - Dev notes describe implementation details that may have changed. Spot-check
   the most recent 3-5 posts for references to functions, classes, or
   architecture that have since been modified.

.agents/skills/datadesigner-docs/SKILL.md

@@ -14,11 +14,11 @@ metadata:
 
 Unified skill for adding, updating, moving, and removing pages on the NeMo Data Designer Fern docs site.
 
-Current URL: **`datadesigner.docs.buildwithfern.com/nemo/datadesigner`** (see `instances` in [`fern/docs.yml`](../../../fern/docs.yml)). Source of truth for everything user-facing is `fern/`.
+Current URL: **`docs.nvidia.com/nemo/datadesigner`** (see `instances` in [`fern/docs.yml`](../../../fern/docs.yml)). Source of truth for everything user-facing is `fern/`.
 
 ## Scope Rule
 
-**ALL doc edits happen under `fern/`.** The legacy `docs/` directory is the original MkDocs source. `docs/notebook_source/*.py` remains canonical for notebook code, but **do not add new top-level prose pages under `docs/`**. Concept pages, recipes, plugins, and Dev Notes prose live under `fern/versions/latest/pages/`.
+**ALL doc prose edits happen under `fern/`.** The remaining `docs/` directory is only for notebook source, generated Colab notebooks, docs scripts, and downloadable recipe scripts. `docs/notebook_source/*.py` remains canonical for notebook code. Concept pages, recipes, plugins, and Dev Notes prose live under `fern/versions/latest/pages/`.
 
 ## Versioning Model
 
@@ -45,7 +45,7 @@ fern/
 ├── fern.config.json           ← organization + fern-api version pin
 ├── main.css                   ← bundled NVIDIA theme CSS
 ├── assets/                    ← logos, favicon, recipe assets, devnote post images (shared)
-├── images/                    ← /images/* references from MDX (mirrors docs/images/)
+├── images/                    ← /images/* references from MDX
 ├── styles/                    ← per-component CSS (notebook-viewer, authors, metrics-table, …)
 ├── components/                ← React/JSX MDX components
 │   ├── NotebookViewer.tsx     ← renders converted .ipynb cells with outputs
@@ -436,7 +436,7 @@ git commit -s -m "docs: <add|update|remove> <page-title>"
 
 DCO sign-off (`-s`) is required by CONTRIBUTING. Use `docs:` prefix (matches recent commit history). Subject line ≤ 50 chars (hard limit 72).
 
-When the team adds a Fern preview workflow (modeled after Gym's `fern-docs-preview-comment.yml`), PRs touching `fern/**` will get an automatic preview URL posted as a comment. Until that lands, share local dev-server screenshots in PR descriptions.
+PRs touching Fern docs inputs get an automatic Fern preview URL posted as a comment. Fork PRs still run checks, but hosted preview publishing is skipped because it requires deployment secrets.
 
 ## Cutting a New Version Train
 
@@ -463,4 +463,4 @@ Do not copy page trees by hand on `main`. The release workflow copies `latest/pa
 
 - Editing Python source under `packages/` — that's a code change, not a docs change.
 - Adding a notebook tutorial's *code*: edit `docs/notebook_source/<name>.py`, not the converted `.ipynb` or the wrapper MDX.
-- Editing dev note *prose*: edit the migrated MDX under `fern/versions/latest/pages/devnotes/posts/<name>.mdx`. (The original `docs/devnotes/posts/<name>.md` is no longer the source of truth — Fern is.)
+- Editing dev note *prose*: edit the MDX under `fern/versions/latest/pages/devnotes/posts/<name>.mdx`.

.agents/skills/review-code/SKILL.md

@@ -97,7 +97,7 @@ Read the following files at the repository root to load the project's standards
 **Documentation sources (load when the changeset touches matching areas):**
 
 - **`architecture/*.md`** — subsystem maps aligned with `packages/` (e.g. `engine/mcp/` ↔ `architecture/mcp.md`). Use to verify the PR does not leave recorded architecture false relative to new behavior.
-- **`docs/`** — published user-facing documentation. Cross-check when public API, CLI behavior, or config surface changes would affect what readers are told.
+- **`fern/versions/latest/pages/`** — published user-facing documentation. Cross-check when public API, CLI behavior, or config surface changes would affect what readers are told.
 
 Use these guidelines as the baseline for the entire review. Project-specific rules take precedence over general best practices.
 
@@ -181,14 +181,14 @@ Re-read the changed files with a focus on **structure and design of the new/modi
 
 **Documentation alignment (same pass — scoped, not a full docs audit):**
 
-When **code** under `packages/` changes behavior, structure, or public contracts in a way that a maintainer would reasonably describe in `architecture/` or `docs/`:
+When **code** under `packages/` changes behavior, structure, or public contracts in a way that a maintainer would reasonably describe in `architecture/` or Fern docs:
 
-1. Identify the closest **`architecture/<topic>.md`** (and any obvious `docs/` pages) for that subsystem.
+1. Identify the closest **`architecture/<topic>.md`** (and any obvious `fern/versions/latest/pages/` pages) for that subsystem.
 2. If the PR **also edits** those docs, sanity-check that the edits match the code.
-3. If the PR **does not** edit docs but the change **contradicts** what `architecture/` or `docs/` currently asserts, flag it (**Warnings** if contributors rely on that text; **Suggestions** if impact is narrow). Suggest updating the same PR or an explicit follow-up issue.
+3. If the PR **does not** edit docs but the change **contradicts** what `architecture/` or Fern docs currently assert, flag it (**Warnings** if contributors rely on that text; **Suggestions** if impact is narrow). Suggest updating the same PR or an explicit follow-up issue.
 4. **Skip** this check for pure refactors with no observable behavior change, typo-only PRs, or changes already limited to documentation.
 
-The local **`search-docs`** skill can help locate `docs/` pages by topic when the right file is not obvious.
+The local **`search-docs`** skill can help locate Fern docs pages by topic when the right file is not obvious.
 
 ### Pass 3: Standards, Testing & Polish
 

.agents/skills/search-docs/SKILL.md

@@ -1,14 +1,14 @@
 ---
 name: search-docs
-description: Search local documentation in the docs/ folder for content related to a topic
+description: Search local Fern documentation for content related to a topic
 argument-hint: <search-topic>
 metadata:
     internal: true
 ---
 
 # Documentation Search
 
-Use the `docs-searcher` subagent to search local documentation for content related to: **$ARGUMENTS**
+Use the `docs-searcher` subagent to search local Fern documentation for content related to: **$ARGUMENTS**
 
 Call the Task tool with:
 - `subagent_type: "docs-searcher"`