Sierra
Sierra is 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.. It is ranked #104 on the Vibe Coding Radar, in Coding agents, first seen 10 days ago and shared in 1 post (15.6k views).
Hyper-𝜏-bench: Evaluating agents that build agents | Sierra Skip to main content Hyper-𝜏-bench: Evaluating agents that build agents Ben Shi Keshav Dhandhania Share September 8, 2026 Subscribe to the Sierra blog Get notified about new product features, customer updates, and more. We built 𝜏-bench in 2024 to answer a question that felt novel at the time: Can a model act as a reliable customer service agent? That’s table stakes now. The harder question is, who’s building the agent in the first place? Increasingly, it’s the models themselves. We’ve partnered closely with some of the world’s leading companies to launch their agents. In…
What people said about Sierra on X
Today we’re releasing hyper-𝜏-bench, a new evaluation that measures how good coding agents are at building agents. 𝜏-bench asked whether models could be good agents. Hyper-𝜏-bench asks whether they can build them. https://sierra.ai/blog/hyper-t-bench-evaluating-agents-that-build-agents
— @SierraPlatform, 10 days ago · 226 likes · see the post
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Sierra in numbers
- Rank on the Vibe Coding Radar: #104 of 141
- Shared in 1 post by 1 account: @SierraPlatform
- 15.6k views on those posts
- First seen 10 days ago, last shared 10 days ago
- Pricing seen by Jev: open source
- Market: Coding agents
FAQ
What is Sierra?
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. It was first shared on X 10 days ago and is ranked #104 on the Vibe Coding Radar.
Is Sierra free?
It is open source.
Who shared Sierra?
1 account on X, including @SierraPlatform, in 1 post totalling 15.6k views.
Every post is read and classified by Jev (TypeSafe): what it is, which market it belongs to, and whether the link is a real tool. 1.8k posts from 1.8k X accounts over the last 14 days, 141 tools, 12 markets. Collected every 5 minutes, fully re-ranked every hour — last update 2026-09-19 01:18 UTC. Full method.