# MDN Web Docs vs OverAPI in 2026

Q: Is AnatomyOf free and open source?

AnatomyOf is free, with no account and no paid tier . It is open source under the MIT License . The sources here state no paid tier for AnatomyOf, so the price they give is free. If you need more detail on future plans, check the project's own pages. Nothing in the claims suggests a fee on top of any other service.

MDN Web Docs, OverAPI and AnatomyOf compared on the reference material each provides, what each costs, and what to check before you choose one.

By SayDeploy · 2026-10-30

SayDeploy is published by LunarWerx, which makes some of the tools compared here.

MDN Web Docs brings its documentation and browser compatibility data into the editor or IDE through an MCP server ^[1]. AnatomyOf shows example source files with color-coded callouts linked to the exact lines they explain ^[2]. The facts given for this page include nothing that describes OverAPI, so check OverAPI's own pages for what it does. MDN's pages also list tools such as a Playground, an HTTP Observatory and generators ^[3]. AnatomyOf is free with no account and no paid tier ^[2], while the sources here state no price for MDN Web Docs or OverAPI.

Option	What it gives	Price	Account	Setup
MDN Web Docs	Documentation and browser compatibility data in the editor through an MCP server ^[1]; tools such as a Playground, an HTTP Observatory and generators ^[3]; documents CSS, HTML and JavaScript since 2005 ^[1]; content in several languages ^[3]	not published	not published	No install step is stated; the MCP server brings the data into the editor ^[1]
OverAPI	not published	not published	not published	not published
AnatomyOf	Example source files with color-coded callouts linked to the exact lines they explain ^[2], with minimal and verbose examples per language ^[2]	free, with no account and no paid tier ^[2]	none needed ^[2]	nothing to install; locally, bun install and bun run dev ^[2]

The short answer

MDN Web Docs brings its documentation and browser compatibility data into a developer's editor or IDE through an MCP server ^[1]. AnatomyOf shows example source files with color-coded callouts linked to the exact lines they explain ^[2]. The facts given for this page describe nothing about OverAPI, so check OverAPI's own pages for what it does.

On needs, MDN's pages list tools such as a Playground, an HTTP Observatory and generators ^[3]. AnatomyOf's claims cover annotated code examples, deeper writeups and diagrams, and the same format applied to non-code concepts ^[2] ^[2] ^[2].

What MDN Web Docs, OverAPI is built for

MDN's MCP server brings MDN's documentation and browser compatibility data directly into the editor or IDE, for use by LLMs and coding agents ^[1]. Its pages list a set of tools, including a Playground, an HTTP Observatory, and a Border-image generator ^[3]. Portions of MDN's content are copyrighted by individual contributors, from 1998 to 2026 ^[1].

The given facts include no description of OverAPI, so this page cannot state what OverAPI does, how it is set up, or what it costs. Check OverAPI's own pages for those details.

What AnatomyOf is built for

AnatomyOf is made by the team that publishes this site.

It shows example source files with color-coded callouts linked to the exact lines they explain ^[2]. Hovering a callout highlights its code, and clicking it opens a longer writeup with a Learn more link ^[2]. Each language has a minimal and a verbose example, and switching between them animates only the lines that change ^[2]. The same annotated format extends to non-code concepts such as an email and a CI pipeline ^[2], and some entries have a third Visual tab with diagrams generated from data and linked to the same annotations ^[2]. The language list is sorted by TIOBE Index rank, can be switched to A-Z, and has instant search ^[2]. Code is highlighted with Shiki, the engine VS Code uses ^[2]. Entries have shareable URLs such as /#/python/verbose ^[2].

Pricing and fees

The sources given here state no price for MDN Web Docs, so a price is not published here. Portions of MDN's content are copyrighted by individual contributors, from 1998 to 2026 ^[1].

The facts here give no price for OverAPI either, so its price is not published here. Check OverAPI's own pages for its cost and licensing.

AnatomyOf is free, with no account and no paid tier ^[2]. It is open source under the MIT License ^[2]. No fee applies on top of any other service.

Setting it up and daily use

MDN Web Docs reaches the editor through its MCP server, which brings documentation and browser compatibility data in for LLMs and coding agents ^[1]. The facts here say nothing more about MDN's setup or daily use.

The sources here give no setup or daily-use detail for OverAPI; check OverAPI's own pages.

AnatomyOf runs in any reasonably current desktop or mobile browser, so there is nothing to install ^[2] ^[2]. To run it locally, use bun install and bun run dev (see Quick start) ^[2]. Daily, you switch a language between minimal and verbose examples, and the change animates only the lines that differ ^[2]. Light and dark themes are available, and on phones you tap to pin a callout ^[2]. Entries have shareable URLs such as /#/python/verbose ^[2]. It sends one anonymous visit ping per browser session on page load, and the README says it collects anonymous usage statistics ^[2]. You add a language by writing one LanguageDef TypeScript file under app/src/data/ ^[2].

Things to check before you choose

Check what reference format you want. MDN's sources describe documentation and browser compatibility data in the editor ^[1] and web tools such as a Playground and generators ^[3]. AnatomyOf's claims describe color-coded callouts on example source files ^[2]. For OverAPI, check its own pages to see what it offers, since the facts here do not describe it.

Check setup. AnatomyOf needs nothing installed to run in a browser ^[2], while MDN's documentation data comes through an MCP server ^[1]; check what your editor supports.

Check cost. The facts here state no price for MDN Web Docs or OverAPI, and AnatomyOf's claims state it is free with no account ^[2].

Check data. AnatomyOf sends one anonymous visit ping per browser session on page load ^[2]; for MDN and OverAPI check their own pages.

How to choose

If you want documentation and browser compatibility data inside your editor for coding agents, MDN's MCP server provides that ^[1].

If you want web tools such as a Playground, an HTTP Observatory and generators, MDN's pages list those ^[3].

If you want example source files with color-coded callouts linked to the exact lines they explain, AnatomyOf's claims describe that ^[2], with a minimal and a verbose example per language ^[2].

If you want a free tool with no account and no paid tier, AnatomyOf's claims say that ^[2].

If you are weighing OverAPI, check its own pages, since the facts here do not describe it.

Frequently asked questions

Is MDN Web Docs free to use?

The sources given for this page do not state a price for MDN Web Docs, so a price is not published here. Portions of MDN's content are copyrighted by individual contributors, from 1998 to 2026 ^[1]. The facts here do not cover how MDN is funded, so check MDN's own pages before relying on it. Whether any part of the service costs money is not stated in the facts given here.

Is AnatomyOf free and open source?

AnatomyOf is free, with no account and no paid tier ^[2]. It is open source under the MIT License ^[2]. The sources here state no paid tier for AnatomyOf, so the price they give is free. If you need more detail on future plans, check the project's own pages. Nothing in the claims suggests a fee on top of any other service.

How do you get MDN Web Docs and AnatomyOf set up?

MDN's MCP server brings its documentation and browser compatibility data into the editor or IDE for LLMs and coding agents ^[1], and the facts here give no further MDN setup steps. AnatomyOf runs in any reasonably current desktop or mobile browser ^[2], so there is nothing to install; to run it locally, use bun install and bun run dev (see Quick start) ^[2]. The facts here give no setup detail for OverAPI.

Can MDN Web Docs work with AI coding tools?

MDN's MCP server brings MDN's documentation and browser compatibility data directly into the editor or IDE, for use by LLMs and coding agents ^[1]. The facts given for this page say nothing about how AnatomyOf or OverAPI connect to AI coding tools, so check their own pages for that. Whether your editor supports an MCP server is something to confirm on your own setup.

Does AnatomyOf send any data about the machine?

AnatomyOf sends one anonymous visit ping per browser session on page load, and the README says it collects anonymous usage statistics ^[2]. For MDN Web Docs and OverAPI, the facts here do not cover data handling, so check their own pages. Confirm your own comfort with that anonymous usage collection before using AnatomyOf in a sensitive setting.

AnatomyOf is free, with no account and no paid tier. ^[2]

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