Notion Developer Platform - Build on Notion, not just inside it

Hi everyone!

Notion used to be a place to work in. Now it’s a place to build on.

This release makes Notion more than a workspace and closer to agent infrastructure. By introducing hosted Workers and a dedicated CLI, developers can now deploy data syncs (like @Zendesk or @Linear) and custom agent tools entirely on Notion's infrastructure.

With External Agents API, you can now bring your own agents—whether it's Claude, Codex, or an in-house build—directly into your workspace. They operate as first-class collaborators that your team can mention, assign tasks to, and review.

The Developer Platform unlocks the full potential of agents for your entire team. What will you build?

Why?
Why not focus on fixing the editor and the slugginess first?!

As a developer .... I feel like Notion is an incredible workspace tool for note-taking, but it is fundamentally not built to be a reliable production database or a headless CMS.

Has anyone actually managed to build a stable, scalable production app on top of Notion without losing their mind?

Think about my biggest pain points:

• Expiring S3 Media URLs == game over

• The block payload is worse than walking on magma

• API Ratelimits is 3/s

What does your caching infrastructure look like?

It’s really pulling me in!

The dedicated CLI for deploying custom agent tools is exactly what was missing for serious builds. I love the idea of agents as first-class collaborators you can actually 'assign' tasks to. Does the API allow the agent to report back its 'reasoning' steps within the Notion comment thread, or is it strictly focused on the final output/task completion?

This looks pretty neat. Can you integrate custom code snippets directly, or is it more about using pre-built templates?