Works with Claude and ChatGPT

Your marketing, from the chat you already use.

Connect Marsen to Claude, ChatGPT or any assistant that supports MCP. Ask how campaigns are doing, start research, or have it draft emails and posts. Marsen does the work in your account and gives you a link to review.

Join the waitlistHow to connect
Your AI assistantMarsen connected
How did last week’s newsletter do? And find 20 more shops like the ones that replied.
Marsen · campaign results
The Spring restock newsletter went to 412 people: 61% opened, 37 replied. Shop owners replied twice as often as buyers.
Marsen · start research
Started: 20 independent bike shops that run group rides, like Cascade Cycle Works and Alder Street. First leads in about an hour.Review in Marsen

Ask in your own words

The assistant picks the right Marsen tool. Anything that would go out to customers comes back as a draft for you to check.

“How did last week’s newsletter do?”

Opens, clicks and replies for each email, and which kinds of people answered.

“Find 20 bike shops in Portland that run group rides.”

Starts research. Marsen works through it in the background and you approve every lead.

“Plan two weeks of LinkedIn and Instagram posts for the fall menu.”

Writes each post for its platform, spread over the weeks, saved as drafts to review and schedule.

“Who replied interested and is still waiting on us?”

The replies, sorted by what people want, each with a suggested answer.

“Start a win-back campaign for customers who bought in spring.”

A draft campaign with the goal set. You choose who gets it and check the emails in Marsen.

“Here’s a list from the trade show. Save it so we can email them.”

Adds the people as a list audience, ready for a campaign.

Connect in a minute

Add Marsen with one address, https://app.marsen.ai/mcp. You sign in to Marsen and pick the project the assistant may use.

Claude

  1. Settings → Connectors → Add custom connector.
  2. Name it Marsen and paste the address.
  3. Connect, sign in to Marsen, choose the project, Allow.

ChatGPT

  1. Settings → Apps & Connectors → turn on Developer mode.
  2. Create an app named Marsen with the address, using OAuth.
  3. Sign in to Marsen, choose the project, Allow.

Claude Code, Cursor and others

  1. Add a remote (HTTP) MCP server with the address.
  2. Sign in through the browser, or use a token from Marsen’s settings.
claude mcp add --transport http marsen https://app.marsen.ai/mcp

Menus in Claude and ChatGPT change from time to time, and some plans need an admin to allow custom connectors. Marsen’s settings always show the current steps.

You stay in charge

It acts as you, in one project, and only drafts

  • Drafts, not sends. Campaigns, research, posts and ad plans come back as drafts with a link to review. Nothing is sent to anyone except an answer to a reply, and assistants ask you first before that or before deleting a research job.
  • Your access, nothing more. The assistant works as you, with your role, in the project you chose when you connected.
  • Disconnect any time. Every connected assistant is listed in Settings with when it was last used. Disconnect it and it stops working right away.
  • No passwords shared. You sign in on Marsen’s own page; the assistant gets a token for that one project.
Settings · AI assistants
ClaudeConnected Oct 8 · used today
ChatGPTConnected Oct 2 · used yesterday
Claude CodeToken · expires in 90 days

Example.

For developers

A remote MCP server over Streamable HTTP, with OAuth 2.1 (dynamic client registration, PKCE) or a bearer token made in Marsen.

get_overviewThe business and how its marketing is doing
list_campaigns · get_campaign_reportCampaigns and their results
create_campaignA draft email campaign
start_research · list_research · get_research · update_researchLead and idea research: start, steer, pause or stop
steer_research · add_research_noteChange direction after a run; notes and marks for the team
update_research_leads · add_research_leads · delete_researchCorrect leads, add ones found elsewhere, delete a job
list_audiences · get_audience · add_people · update_audienceAudiences: new lists, rename, add or remove people
list_replies · answer_replyReplies, and answering one (after you confirm)
plan_social_campaign · create_social_post · list_social_postsSocial posts as drafts
create_ad_planAd plans, where turned on
search · fetchFind and open anything above

Bring Marsen into your assistant.

Join the waitlist. When your spot opens, connect Claude or ChatGPT in Settings and start asking.

Join the waitlist