Introducing SteelThread: Evals & Observability for Reliable Agents

We’ve spent a lot of time internally running evals for our own agents. If you care about reliability in agentic systems, you know why this matters — models drift, prompts change, third party MCP tools get updated. A small change in one place can cause unexpected behavior somewhere else.

That’s why we’re excited to share something we’ve been using ourselves for months: SteelThread, our evaluation framework built on top of Portia Cloud.

You can try if for free on or check out our GitHub repo!