Every rule, in the open.

One source: the official registry.

Every listing comes from the public API of the official MCP Registry at registry.modelcontextprotocol.io (/v0/servers, latest versions only, read 100 at a time). Nothing is added by hand and nothing is removed by hand. A server must be marked active in the registry to appear.

Every field shown is a fact from the registry record or from one request we make ourselves: the name, the publisher, the description in the publisher’s own words, remote or local, the declared auth, the registry link and the date the registry last updated it. There are no ratings, reviews or rankings by quality.

Refreshed every day.

A scheduled job runs every day at 10:27 UTC. It reads what changed in the registry since the last run, with a two hour overlap, and once a week it rereads the whole registry and drops any server that is no longer active or no longer matches. When the map below changes, the next run rereads everything.

What counts as small business.

A server is listed when its title, description or name matches at least one strong term of a category (a product name or an unambiguous phrase), or two different weak terms of the same category (words that mean something else alone). Terms match whole words, ignoring case, with an optional plural. A server can sit in more than one category. General productivity and developer tools are out of scope unless they name a small business job.

Trades, from the text.

A listed server is tagged with the trades its category serves and with any trade its own text names. The trade terms:

Never listed.

A server whose text matches any of these terms is left out, whatever else it matches: crypto, cryptocurrency, blockchain, web3, defi, nft, solana, ethereum, bitcoin, btc, eth, onchain, on-chain, token swap, memecoin, x402, usdc, stablecoin, polymarket, prediction market, stock trading, trading bot, forex, options trading, code review, pull request, kubernetes, terraform, mcp server template, boilerplate, hello world, casino, betting, gambling, adult content, synthetic cases, benchmark cases. Servers that declare a pay-per-call header (payment-signature, x-payment) are left out too, because they charge the agent per request rather than signing in a business.

Official or community.

Every registry name starts with a namespace. A domain namespace, like com.example, can only be published by someone who proved they own that domain. A GitHub or GitLab namespace, like io.github.someone, proves an account, not a company.

• Official: a domain namespace, and the connector URL or website is on that same domain, and the server is not named after another company’s product. A server whose only links are code hosts is judged by its namespace alone.
• Community: everything else. That includes every GitHub or GitLab account namespace, and a connector for a product published by anyone other than its maker, wherever it is hosted.
• Catalog publishers: a domain with 15 or more servers in the directory publishes connectors for other companies’ products. Its servers count as official only when they are named after the publisher itself.

The products we recognize by name, and the domains of the companies that make them:

jobber (getjobber.com, jobber.com); housecall pro (housecallpro.com); servicetitan (servicetitan.com); servicem8 (servicem8.com); workiz (workiz.com); fieldedge (fieldedge.com); tradify (tradifyhq.com); buildertrend (buildertrend.com, buildertrend.net); companycam (companycam.com); jobnimbus (jobnimbus.com); acculynx (acculynx.com); procore (procore.com); calendly (calendly.com); acuity scheduling (acuityscheduling.com, squarespace.com); cal.com (cal.com); setmore (setmore.com); google calendar (google.com); google ads (google.com); google analytics (google.com); google business profile (google.com); google my business (google.com); search console (google.com); google forms (google.com); google reviews (google.com); outlook calendar (microsoft.com); microsoft bookings (microsoft.com); stripe (stripe.com); paypal (paypal.com); square payments (squareup.com, square.com, block.xyz); square pos (squareup.com, square.com, block.xyz); quickbooks (intuit.com, quickbooks.com); xero (xero.com); freshbooks (freshbooks.com); zoho (zoho.com); netsuite (netsuite.com, oracle.com); expensify (expensify.com); hubspot (hubspot.com); salesforce (salesforce.com); pipedrive (pipedrive.com); keap (keap.com); gohighlevel (gohighlevel.com, highlevel.com, leadconnectorhq.com); highlevel (gohighlevel.com, highlevel.com, leadconnectorhq.com); follow up boss (followupboss.com); freshsales (freshworks.com); freshdesk (freshworks.com); attio (attio.com); clover (clover.com, fiserv.com); toasttab (toasttab.com); toast pos (toasttab.com); lightspeed (lightspeedhq.com); shopify (shopify.com, shopify.dev); woocommerce (woocommerce.com, automattic.com, woo.com); bigcommerce (bigcommerce.com); etsy (etsy.com); printify (printify.com); printful (printful.com); shipstation (shipstation.com); shippo (goshippo.com, shippo.com); easypost (easypost.com); mailchimp (mailchimp.com, intuit.com); klaviyo (klaviyo.com); constant contact (constantcontact.com); brevo (brevo.com); activecampaign (activecampaign.com); mailerlite (mailerlite.com); beehiiv (beehiiv.com); omnisend (omnisend.com); instagram (meta.com, facebook.com, instagram.com); facebook ads (meta.com, facebook.com); meta ads (meta.com, facebook.com); tiktok (tiktok.com, bytedance.com); pinterest (pinterest.com); hootsuite (hootsuite.com); sprout social (sproutsocial.com); yelp (yelp.com); trustpilot (trustpilot.com); birdeye (birdeye.com); podium (podium.com); wordpress (wordpress.com, wordpress.org, automattic.com); wix (wix.com); squarespace (squarespace.com); webflow (webflow.com); godaddy (godaddy.com); zendesk (zendesk.com); intercom (intercom.com, intercom.io); help scout (helpscout.com, helpscout.net); gorgias (gorgias.com); twilio (twilio.com); ringcentral (ringcentral.com); dialpad (dialpad.com); openphone (openphone.com, quo.com); aircall (aircall.io); zillow (zillow.com); redfin (redfin.com); appfolio (appfolio.com); buildium (buildium.com); hostaway (hostaway.com); guesty (guesty.com); airbnb (airbnb.com); clio manage (clio.com); clio grow (clio.com); mycase (mycase.com); filevine (filevine.com); planning center (planningcenter.com, planningcenteronline.com); pushpay (pushpay.com); opentable (opentable.com); resy (resy.com); doordash (doordash.com); gusto (gusto.com); adp (adp.com); rippling (rippling.com); paychex (paychex.com); bamboohr (bamboohr.com); docusign (docusign.com, docusign.net); pandadoc (pandadoc.com); typeform (typeform.com); jotform (jotform.com); surveymonkey (surveymonkey.com); mindbody (mindbodyonline.com, mindbody.io); vagaro (vagaro.com); simplepractice (simplepractice.com).

Auth: what it says and what it asked.

• When the registry declares a secret header or setting, the auth column names it: a key in a header, a token, or a key in a setting.
• When a remote server declares nothing, we send it one MCP initialize request, at most once every 30 days, only to a public internet address and without following redirects. A 401 that points to OAuth metadata or asks for a Bearer token reads “Sign in with your account (OAuth)”. Any other 401 or 403 reads “Sign-in required, method not stated”. A success reads “No sign-in”. Anything else reads “Not declared in the registry”.
• A local server with no secret declared reads “None declared”: it runs on your computer with whatever access you give it.

One order for everyone.

Inside every category: official first, then connectors that work by URL, then the most recently updated in the registry, then alphabetical by registry name. No listing is placed by hand. Modern Mustard Seed builds connectors, and ours are in this directory. They are sorted by the same rules as every other listing, nobody pays to be listed or placed, and no listing is a review or a recommendation.

Where the makers are missing.

The coverage section on the directory home lists categories with fewer than 10 official connectors. It reports counts only. It never names a company as lacking a connector.

Text handling.

Registry text is untrusted input. Markup and control characters are stripped, long descriptions are shortened, links are kept only when they are https, and every outbound link carries nofollow. This site shows no prices, so a link whose address carries a price is left off, and any price in a title, description or auth note, in any currency, written with a symbol, a code or a word, is replaced with “(price on the publisher’s site)”, and an em dash is shown as a comma.

Corrections.

If a listing is wrong, write to sarah@modernmustardseed.com. We fix the rule, not the listing, so the fix applies to everyone. To change your own description, publish a new version to the registry; the directory follows within a day.

Claude is a product of Anthropic, and ChatGPT is a product of OpenAI. Modern Mustard Seed is an independent studio and is not affiliated with or endorsed by either. The MCP Registry is run by the Model Context Protocol project; this directory reads its public API.