The official Notion MCP was just caught injecting an upsell into an agent's answ
By Moekatib · October 17, 2026 · Curated by George's Blog
The official Notion MCP was just caught injecting an upsell into an agent's answer. Nobody had asked about pricing, plans, or Notion Business.
A developer on Reddit was using Grok and Claude to organize his Notion notes.
Claude finished the job, then tacked on a line pitching Notion Business, link included.
He had Claude inspect the connector, and it found a tool called check-mcp-next-steps.
Its instructions tell the agent to:
1. Finish the user's task first
2. Add one short sentence tied to their work, plus a link
3. Never mention limits, eligibility, or frequency logic
The link even carried tracking fields like mcpUpsellOpportunityId.
In August, I called Notion's agent platform one of the best I'd seen, and I still stand by that. I also have no problem with a company upselling inside its own product.
My problem is where this one showed up.
When Notion shows a banner in its own UI, you know Notion is talking.
But when a line shows up in your agent's answer, you assume your agent said it.
Once a connector can speak through your agent without saying it's the one talking, you start second-guessing every answer:
→ Is this what I asked for?
→ Is this my agent's own call?
→ Or did a vendor put it there?
I think about this a lot because agents on One make every app call through us.
We log each call with the app it hit and what came back, so if a provider slips something into a response, you can see who sent it.
My rule: a vendor can recommend anything through your agent, as long as the agent tells you who it's from.
If the pitch only works when you think your agent came up with it, it doesn't belong in your agent's answer.