Claude MCP connector for on-brand writing, decks and images

Add the Rainbrand connector

Anthropic calls an MCP server connected to Claude a connector. You add Rainbrand as a custom connector, by its server address, in claude.ai or the Claude desktop app.

The link opens Customize > Connectors with the Add custom connector dialog filled in: the name Rainbrand and the address https://mcp.rainbrand.com/mcp. Claude notes that the values came from a link, so check them and select Continue. Then select Connect and sign in to Rainbrand, or create an account. Rainbrand appears under Your connectors with the Custom label.

Connectors are switched on per chat. Select + in the message box, then Connectors, and check that Rainbrand is on. The first time Claude calls one of Rainbrand's tools, it asks you to allow it. Always allow stops the prompts for that tool, and you can change this tool by tool on Rainbrand's page under Customize > Connectors.

Then start a new chat and check which account is connected. If you use more than one Rainbrand account, do this first.

Show me which Rainbrand account is connected.

Which plans can use it

Custom connectors work in claude.ai, the desktop app and Cowork on every Claude plan. Once Rainbrand is connected, it's in your chats on the web, desktop and mobile apps.

Free

You can add one custom connector, so Rainbrand takes your only slot.

Pro and Max

You add Rainbrand yourself.

Team

An Owner or Primary Owner adds Rainbrand under Organization settings > Connectors. Each member then connects it with their own Rainbrand account.

Enterprise

As on Team. Members whose custom role can manage the organisation's libraries can add it too.

On Team and Enterprise, members without those roles can't add custom connectors, so the link is for Owners. Owners can also use the organisation version of the link, which fills in the same dialog in organisation settings.

Pick a brand, or add one

If your team already has brands in Rainbrand, ask Claude to list them. To add one, give Claude what defines it: a website, a brand guide, written rules, logos or images. Upload files through Rainbrand's file picker, which opens in the chat. A brand is usually ready in about 90 seconds.

Add a brand in Rainbrand from [your website] and the files I upload. Open Rainbrand's file picker for the files. Wait until the brand is ready, then show me its name and a summary of its guidance.

Write the update email

I gave Claude a job where the facts had to be right: an update to Heart Aerospace's investors and airline partners on August to October 2026, built from Heart's own newsroom. I added Heart Aerospace to Rainbrand first, from heartaerospace.com, its X1 press release, its logo and its brand kit.

One Brief covers the whole update, because the email, the deck and its cover share the same audience and facts.

Request a Rainbrand Brief for Heart Aerospace. The task is an update to Heart's investors and airline partners on August to October 2026: an email of about 250 words, then a five-slide 16:9 deck with a cover image of the ES-36. It covers three announcements on heartaerospace.com/newsroom: X1's first flight, the ES-36 unveiling with JSX's purchase agreement, and the FAA CLEEN award. Wait for the Brief and show me its guidance and files. Then write the email using it, and check every fact against Heart's newsroom.

The Brief described Heart's voice as concise, declarative and confident: lead with the practical outcome, lower-cost regional flying, then explain the engineering behind it. It kept X1's test results apart from what the ES-36 is planned to do, allowed "zero emissions" only for all-electric routes, and tied the 40% operating-cost claim to entry into service. It also said the brand's files don't confirm the three announcements, so the dates and terms had to come from the newsroom.

Claude then checked each fact against the newsroom and listed what it left out on purpose: luggage and charging figures the Brief mentioned but the releases don't, and a customer-commitment total that the releases give two ways.

Make the cover image

Claude doesn't make photos or illustrations itself, so the cover comes through Rainbrand's AI Gateway. That uses Rainbrand credits, and the image is saved to Rainbrand, where a Review can check it. The Brief said Heart's brand has no ES-36 image and labelled its only 16:9 aircraft photo an ES-30. Claude spotted that the photo shows "ES-36" and two nacelles, so the label was wrong, and took the aircraft from an ES-36 side-profile render in another Heart Aerospace brand on the same team. A generated ES-36 in the sky mustn't be passed off as a photo, so the deck labels it a concept render.

Make the 16:9 cover through Rainbrand's AI Gateway with Nano Banana 2.1 and the same Brief: a concept render of the ES-36 in flight above cloud in early light. Take the aircraft and its markings from the side-profile render, and leave open sky on the left for the title. Then request a Review for colour, typography, logo and copy, and fix what it finds.

First try2 fail · 2 uncertain

→

After two edits1 pass · 3 uncertain

The first Review failed copy and colour. The small "Heart Aerospace" lettering by the cockpit came out garbled, and the dawn light gave the white and grey paint a blue-purple cast. Claude neutralised the paint with an edit. A second edit still garbled the lettering, so Claude removed it and kept only the symbol. It also caught something no check covers: the visible wing's tip light was green, and on the left wing it should be red.

The second Review passed copy. Colour, logo and typography came back uncertain, because markings painted on a curved, lit fuselage can't be measured against flat brand swatches. On a render like this, the Review catches wrong words and colour casts but won't confirm the logo, and it doesn't check whether the aircraft is drawn right, so compare that with the render yourself.

Copy

First: fail, the lettering by the cockpit was garbled. After: pass.

Colour

First: fail, a blue-purple cast on the white and grey paint. After: uncertain.

Logo

First and after: uncertain.

Typography

First and after: uncertain.

Build the five-slide deck

Claude makes PowerPoint files in its code sandbox. The Brief already covers the slides: black and white with two greys, Neue Haas Grotesk Display Bold for headlines and Text Regular for body copy, with links to the font files. Heart's logo has no white version, so the black lockup only goes on a light area.

Now build the update as a five-slide 16:9 PowerPoint deck: title, X1's first flight, the ES-36 and JSX, the CLEEN award, and what's next. Follow the Brief for colours, fonts and logos. Put the fixed cover on the title slide and label it 'Concept render'.

The cover and the logo made it into the file. The fonts didn't: the deck names Neue Haas Grotesk but doesn't embed it, so the type shows in that face only on computers that have it installed. If Claude's sandbox can't download a file from www.rainbrand.com, an Owner on Team and Enterprise can allow the domain under Organization settings > Capabilities.

Why not keep the brand in a Claude Project or skill?

Claude has three places to keep a brand, and each does part of the job. Projects are on every plan: a Project holds instructions and files that every chat in it uses, and on Team and Enterprise you can share one. A skill is a folder of instructions, scripts and files that Claude loads when a task matches it. It can carry your logo files and fonts, and when you update a skill you've shared, colleagues get the new version the next time they use it. A design system, in beta on paid plans, captures colours, type, components and layouts, and Claude applies it to designs and decks.

None of the three reaches past Claude on its own. A Project's instructions and files reach only the chats in that project. A skill you add in claude.ai also loads in Claude Code when you sign in with the same account, but Anthropic's API docs say custom skills don't sync across surfaces: a skill uploaded to claude.ai has to be uploaded again to use through the API. Cursor and Codex can read the same skill format, but you install and update a copy in each.

A brand in Rainbrand is one source for every agent you connect: Claude, ChatGPT, Cursor, Codex, and your own product through the API. When the brand changes, you edit it once, and each agent uses the new version on its next task. Rainbrand builds it from a PDF or your website in about 90 seconds on average, and each Brief sends only what the task needs. For this update, that was two of the 112 images in Heart's brand. Keep campaign facts and drafts in a Project if you like, and ask for the Brief inside it.

What it can't do in Claude

Files you attach to a Claude message stay in Claude, and Rainbrand can't open them, so use Rainbrand's file picker in the chat or a public link. Reviews check images, including the words in them, but not the text of an email, and not whether an aircraft or a product is drawn correctly. Rainbrand is a custom connector, and Claude never suggests custom connectors on its own, so switch it on in the chat or ask for Rainbrand by name. Rainbrand doesn't read or change your Projects, skills or design systems in Claude. To move a brand out of one, add it to Rainbrand once from its files, with its written rules as guidance.

Fix common problems

You can't add the connector

On Team and Enterprise, ask an Owner to add it with the organisation link above. On Free, you can have one custom connector, so remove the other one first.

Claude answers without Rainbrand

Select +, then Connectors, and switch Rainbrand on for this chat, or ask for a Rainbrand Brief by name.

Claude asks before every Rainbrand tool

Choose Always allow, or set permissions tool by tool on Rainbrand's page under Customize > Connectors.

A Brief or brand is still processing

Claude stops waiting on a tool after 240 seconds, but the work carries on in Rainbrand. Ask Claude to check the same Brief or brand again. Starting the task over can create a duplicate.

Rainbrand can't open a file

Upload it through Rainbrand's file picker or share a public link. Files attached to a Claude message aren't reachable.

Rainbrand shows Reconnect

Select Reconnect under Customize > Connectors and sign in to Rainbrand again.

Out of credits

Follow the link in the message to add credits or upgrade.

More fixes are in Rainbrand's troubleshooting guide.

Questions

Does the connector work in Claude Code?

Yes. Connectors you add in claude.ai are available in Claude Code when you sign in there with the same Claude account, in the terminal and in cloud sessions. Claude Code also has a Rainbrand plugin with the Skill and the connection together; see Rainbrand in Claude Code.

Is a connector the same as a skill or a plugin?

No. A connector links Claude to a service over MCP, a skill is instructions Claude loads for a task, and a plugin packages skills and connectors into one install. Rainbrand's Briefs, Reviews and generation come through the connector.

Does it work in the Claude mobile app?

Yes. Once Rainbrand is connected, it's available in your chats on the web, desktop and mobile apps.

Can my team use the same brands?

Yes. Brands in a Rainbrand team are available to everyone in it, in whichever agent they connect. In Claude, each person connects Rainbrand with their own Rainbrand account.

What does it cost?

Your Claude plan covers Claude. The connector works on every Rainbrand plan, and Briefs, Reviews and generations through Rainbrand use Rainbrand credits. Plans and credit prices are on our pricing page.