Sierra

Introducing fleming-1, Sierra’s own model for detecting when the caller on a phone call is another agent.

AI is moving faster than anyone predicted. At Sierra Summit, we shared how Sierra helps companies stay on the frontier, stay in control as personal agents arrive, and turn customer context into a lasting advantage.

We’re excited to announce Personal Agent Protocol — an open standard Meta and Sierra are developing along with industry partners at Genesys, Instinct, Rocket, Shopify, Stripe, and Walmart that defines how personal agents interact with businesses.

Today we’re introducing Sierra’s partner ecosystem: the technology platforms, marketplaces, and service partners bringing Sierra to more businesses worldwide.

We’re excited to be a launch partner in OpenAI’s new marketplace. Now, eligible customers can build agents with Sierra using their OpenAI commitments.

Ghostwriter now works alongside your team in Slack and Teams — always on, proactive, and asynchronous. It moves past "I did what you asked" to "I noticed something you should see" and "I have an idea we haven't tried."

Material Event filed 2026-09-23

For decades, enterprise software was a black box — hard for companies to understand, implement, adapt, and integrate, or even replace. With Sierra, nothing is hidden. It’s easy to build an agent, understand the actions it takes, integrate it with existing systems, and make changes directly.

Sierra is now AIUC-1 certified, following an independent audit by Schellman and extensive testing by the Artificial Intelligence Underwriting Company (AIUC).

Sierra’s multimodal agents bring voice, text, and visuals into the same conversation, so customers get the best of each medium without having to pick just one.

Today we’re open-sourcing hyper-𝜏-bench, a new long horizon agent evaluation that measures how well models can not only act as an agent, but construct one.