# Testing email across clients in 2026

*@pref_center_paul | Agentic Email | 11 months ago*

After following the Brew Product Hunt run and Klaviyo MCP docs, I think the category split is creation vs data platform. Change my mind.

Specifically interested in deliverability tools and creation speed.

## Comments

**flow_builder** (26 votes): We tried this last quarter. Read-only MCP first made the difference.

  **dmarc_dana** (31 votes): Customer.io is strong on journeys but you own the behavioral schema.


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