Stainless: vendor profile

In short

Stainless builds a docs site as a static Astro and Starlight project and serves each page as markdown by Accept header or at /index.md. A team first needs one Stainless-generated SDK. Its marketing site answered unknown paths with its homepage and 200 on 2026-11-05. Free covers up to 5 generators.

At a glance

standards.txt stainless

llms-txt               = no statement
markdown-negotiation   = supports
markdown-twin          = supports
initial-html           = supports
real-404               = no statement
vary-accept            = no statement

3 supports, 0 partial or announced, 3 no statement.

Stainless Docs platform

SDK generator vendor whose Docs Platform (public beta since March 2026) builds each docs site as a static Astro and Starlight project with API and SDK reference, a markdown copy of every page at /index.md, and AI chat; it needs at least one Stainless SDK.

Type: Docs platform
Home page: www.stainless.com, answered HTTP 200 on 2026-11-05
Last read: 5 November 2026

What it does for this layer

Stainless labels its Docs Platform a public beta and warns of breaking API changes before version 1.0. [primary source] source, read 5 November 2026.
Each Stainless Docs Platform site is a standalone Astro project in a Git repository the customer controls, and Astro outputs static HTML and CSS with opt-in interactive islands. [primary source] source, read 5 November 2026.
The Stainless Docs Platform writes a markdown version of every page on the site, reached by adding a .md extension to the URL. [primary source] source, read 5 November 2026.
Stainless's public beta post of 2026-03-12 says every docs page is served as markdown through the Accept header or at /index.md, with SDK method signatures in the endpoint pages. [primary source, 2026-03-12] source, read 5 November 2026.
Stainless first opened its Docs Platform in early access on 2025-11-05, describing it as built on Astro with hosting on Cloudflare. [primary source, 2025-11-05] source, read 5 November 2026.
The Stainless Docs Platform currently requires at least one Stainless-generated SDK; Stainless says that requirement should go away by 1.0. [primary source, 2026-03-12] source, read 5 November 2026.
Stainless docs sites can move off Stainless hosting to any static host such as Cloudflare Pages, Vercel, Netlify or GitHub Pages, given @stainless-api/docs 1.0.0-beta.143 or newer. [primary source] source, read 5 November 2026.
Stainless Docs uses Starlight's Pagefind index for guide search and offers optional Algolia search over the API reference; the beta post adds a vector search layer. [primary source] source, read 5 November 2026.
Stainless's pricing page counts a docs site as one generator; the Free plan at $0 covers up to 5 generators, and the docs feature list includes custom domain, AI markdown rendering, AI chat and password-protected docs. [primary source, 2026-11-05] source, read 5 November 2026.
Stainless says its SDK generator serves API companies including Anthropic, Cloudflare and OpenAI. [vendor claim] source, read 5 November 2026.
On 2026-11-05 Stainless's own docs at www.stainless.com/docs (generator meta Astro v6.3.1 and Starlight v0.38.5) served /docs/docs-platform/index.md as text/markdown at 6,256 bytes but answered Accept: text/markdown on the page URL with HTML. [observed, 2026-11-05] source, read 5 November 2026.
On 2026-11-05 a made-up path under www.stainless.com/docs/ returned HTTP 404, while the marketing site returned HTTP 200 with its homepage for unknown paths, including /llms.txt. [observed, 2026-11-05] source, read 5 November 2026.

Products and plans

Plans and prices as the vendor's own pages showed them on the date read.
Product	What it is	Price	As of	Source
Stainless Docs Platform	Astro and Starlight based docs framework and hosting that unifies API reference, SDK reference and MDX guides, in public beta.	Free tier, paid plans above it Free plan $0 for up to 5 generators (an SDK, docs site or MCP server each); Starter, Pro and Enterprise prices were not in the fetched HTML.	2026-11-05	source

Standards

The six standards this site tracks; no statement means the pages read said nothing.
Standard	Status	What the vendor's pages say	Source
llms-txt	no statement	No llms.txt statement found in the Docs Platform overview, hosting or configuration pages or the two launch posts; Stainless's own docs serve /docs/llms.txt.	none
markdown-negotiation	supports	Beta post says every page is available as markdown via the Accept header; Stainless's own docs returned HTML for Accept: text/markdown on 2026-11-05.	source
markdown-twin	supports	Markdown version of every page by adding .md (or /index.md) to the URL.	source
initial-html	supports	Sites are Astro projects that generate static HTML; hosting docs call them multi-page static sites.	source
real-404	no statement	No 404 statement found in the routing or hosting pages; an unknown path under www.stainless.com/docs/docs-platform/ answered 404 on 2026-11-05.	none
vary-accept	no statement	Stainless's docs pages do not cover response headers, and www.stainless.com/docs sent no Vary header on 2026-11-05.	none

Checks on its own site

Readings of stainless.com, the vendor's own website, which describe that site and not the product.
Reading	Result	Date
Home page request	HTTP 200; H1 in the initial HTML: yes; 211 words; 0 JSON-LD blocks	2026-11-05
Request with Accept: text/markdown	HTTP 200, text/html, Vary: accept-encoding	2026-11-05
/llms.txt at the host root	HTTP 200, text/html, 683 KB	2026-11-05
A made-up path	HTTP 200	2026-11-05
Ora score, cached	58, grade C	2026-09-10
Cloudflare keyless scan	20, L1 Basic Web Presence	2026-11-05

What it does not do

Stainless's Docs Platform pages make no llms.txt promise, even though Stainless's own docs serve /docs/llms.txt.

Related pages on this site

Sources

Stainless: home page https://www.stainless.com/, read 5 November 2026
Stainless Docs Platform overview | Stainless https://www.stainless.com/docs/docs-platform/, read 5 November 2026
Stainless - Blog - Stainless Docs Platform: now in public beta https://www.stainless.com/blog/stainless-docs-public-beta/, read 5 November 2026
Stainless - Blog - Stainless Docs Platform is now available in early access https://www.stainless.com/blog/stainless-docs-early-access/, read 5 November 2026
Hosting and deploys | Stainless https://www.stainless.com/docs/docs-platform/hosting-and-deploys/, read 5 November 2026
Stainless - Pricing - Get the pricing that’s right for your API. https://www.stainless.com/pricing, read 5 November 2026

Last reviewed 5 November 2026