Connect Claude to Book a Sponsor: a guide for newsletter publishers
For newsletter publishers: to connect Claude to Book a Sponsor, add https://bookasponsor.com/mcp as a custom connector and choose No sign in. In Claude Code, run one command. Claude can then list the brands that sponsored newsletters like yours and read median rates, from 8,550 brands in 4,988 newsletters. It can't send pitches.
Run on 6 November 2026 in Claude Code 2.1.318 against the live server. We read the claude.ai steps from Anthropic's help page and didn't click through them ourselves.
Book a Sponsor (bookasponsor.com) pitches brands to sponsor newsletters.
Quick picks: what are you doing?
| You use | Do this | Note |
|---|---|---|
| Claude on the web or desktop | Add a custom connector | Claude's Free plan allows one |
| Claude Code | One command in a terminal | We ran this one |
| ChatGPT | Connect ChatGPT instead | Depends on your plan |
| No AI assistant | Paste your newsletter on the home page | The same data, free |
How do you add it in Claude on the web or desktop?
Six steps, from Anthropic's help page for Pro and Max plans; we haven't clicked through them, so a screen may have moved. On Team and Enterprise, an owner adds it under Organization settings, Connectors.
- Open Customize, then Connectors, on claude.ai. You should see your connector list.
- Select + Add, then Add custom connector. A form should ask for a name and a URL.
- Enter a name and the URL, then Continue. Name it Book a Sponsor and paste
https://bookasponsor.com/mcp. - Review the settings Claude detected, then Continue. This server has no sign-in, so there is nothing to change here.
- Under Authentication, choose No sign in, because this server has no accounts. Then select Add.
- Turn it on in a chat. Select + at the lower left of the chat, choose Connectors and switch it on. Claude can then use the four tools below.
How do you add it in Claude Code?
Run this in a terminal. We ran it on 6 November 2026, and claude mcp list then printed the second block.
claude mcp add --transport http book-a-sponsor https://bookasponsor.com/mcp
book-a-sponsor: https://bookasponsor.com/mcp (HTTP) - ✔ Connected
What does it return? A real prompt and answer
We asked this in Claude Code with a small model, once, on 6 November 2026. The answer is copied as it came back.
Which brands sponsor newsletters like growthdives.com? Answer in 5 lines at most.
Book a Sponsor found 256 brands that sponsor similar business newsletters. The closest fits: - Atlassian (12 sponsorships, most recent Oct 2026) - Figma, Replit, Pitch, Product Faculty, Flourish, Carta Launch, founderdash.com (each 1 sponsorship) - Full list: https://bookasponsor.com/run/growthdives.com These are sponsors of similar newsletters, not confirmed sponsors of growthdives.com itself.
Your answers will read differently, because the model writes them. The data under them comes from the same server. Other prompts to try: "What should a newsletter with 12,000 subscribers charge for a main slot?" and "Which brands buy the most newsletter ads in AI?"
What can Claude do with it?
| Tool | Input | What it returns |
|---|---|---|
find_newsletter_sponsors | newsletter_url | Brands that sponsored newsletters like yours, with where and when their ads ran. Starts a scan if none exists: 15 to 60 seconds |
get_sponsor_scan | newsletter_url | Reads a scan back when the first call said it was still running |
list_brands_sponsoring_newsletters | niche (optional) | The brands seen in the most newsletters, overall or for one topic |
get_newsletter_sponsorship_rates | subscribers (optional) | The median printed price of a main slot by list size, with the middle half |
What can't Claude do with it?
- It returns brands, never people: no buyer names, email addresses or drafted pitches come through this server.
- It can't send a pitch, sign you up, read your account or see your dash. The results link opens your run on bookasponsor.com.
- A scan lists the 8 closest fits, with the total count. The rest are on the results page.
- A new newsletter's scan can take up to a minute, and the same refusals as the website apply, such as adult content.
Questions
Does connecting Claude to Book a Sponsor cost anything?
No. The server needs no account, key or card. Claude's Free plan allows one custom connector. Daily pitches are a separate product: a plan from $19 a month after the first 200 emails, which come with a $1 card check.
Can Claude send pitches to sponsors through this?
No. It reads data only. To have brands emailed, start from your run page. Book a Sponsor sends them on a plan from $19 a month.
Why does Claude call the server sponsor-radar?
That is the server's internal name from before the product was renamed Sponsor Radar to Book a Sponsor. The name you type when you add the connector is the one you see.
Does it work in Claude Desktop?
Anthropic's help page lists custom connectors for Claude, Cowork and Claude Desktop. Add it once on claude.ai and it follows your account, and Claude Code loads connectors from that account when you sign in with it.
Sources
- Anthropic: get started with custom connectors using remote MCP, read 6 November 2026
- Claude Code: connect to tools via MCP, read 6 November 2026
- Book a Sponsor MCP server reference, read 6 November 2026
Have those brands pitched for you
Paste your newsletter. Book a Sponsor lists the brands that sponsored newsletters like yours, finds the person who buys the ads, and emails them every day from its own mailboxes. You get the replies and close the deal.
$1 card check gets 200 emails, then a plan from $19/mo · first sponsor reply inside 30 days or your money back