Hue

Key facts: Hue builds a fake but realistic copy of the world your agent works in. Describe it, for example a 15-person startup that uses Gmail, Notion and Slack, and Hue fills it with months of believable data, or rebuilds it from your agent's real traces. Each run gets its own world that keeps every change and resets easily, and you score runs to compare agent versions. Your agent connects the way it would to the real apps, through API, MCP, Composio or Pipedream. It is part of Y Combinator's Fall 2026 batch.

Plans: Pricing is not listed on the site.

Best for: Teams building agents that work across email, docs, chat and CRM tools. Who should skip it: teams whose agents only touch one simple API.

Pros

• Realistic simulated worlds with months of believable data, built from a description or real traces
• Each run is isolated, keeps every change, and resets easily
• Score runs to compare agent versions side by side
• Agents connect through API, MCP, Composio or Pipedream, just like the real apps

Watch out for

• Pricing is not listed on the site
• A simulated world is still a model of reality, so final checks on real data remain necessary
• A new Y Combinator product with a maturing feature set

Best for

Teams building agents that work across email, docs, chat and CRM tools. Who should skip it: teams whose agents only touch one simple API.

Pricing

Pricing is not listed on the site. Check the official site for current plans.

FAQs

What does Hue build? A fake but realistic copy of the world your agent works in, filled with months of believable data.

Can it rebuild from my real data? Yes, it can rebuild a world from your agent's real traces.

How do I compare agent versions? Score runs in separate worlds and compare them.

How does my agent connect? Through API, MCP, Composio or Pipedream, the way it would to the real apps.