Sierra
Sierra builds branded voice and chat agents for support, charging per resolved conversation rather than per seat.
Full Sierra record →Head to head
Sierra vs Browser Use
Sierra (Sierra) and Browser Use (Browser Use) both sit in Agents & Automation. Browser Use shipped more tracked changes in the last 30 days (19 vs 0). Every value below comes from the latest crawl of the vendors' own pages.
| Attribute | Sierra Sierra | Browser Use Browser Use |
|---|---|---|
| Segment | Agents & Automation | Agents & Automation |
| Version | Agent OS 2.0 | API v4 |
| Entry cost | Pricing is outcomes-based (pay for results, not tokens), contact Sierra for custom pricing. | Pay as you go (no subscription). Free tier offers $1 signup credit. Cloud browser from $0.02/hr + traffic. |
| Pricing tiers | Outcome pricing free | Free / Sign up free · Pay as you go free · Enterprise free |
| Model stack | Claude · fleming-1 · GPT-5 class · OpenAI models · Sierra Agent OS 2.0 | Bring your own key · BU 2.0 · BU Fast · BU Ultrafast · Claude Opus 5 · Claude Opus 5.5 · Claude Sonnet 5 · Claude Sonnet 5.5 · Gemini 3.6 Flash · GLM 5.3 Flash · GPT-5.6 · GPT-5.6 Luna · GPT-6 Astra · GPT-6 Luna · GPT-6 Sol · GPT-6.1 Sol · GPT-6.1 Terra · Grok 4.5 · Grok 4.6 · MiniMax M3 |
| Context window | Model-dependent | Depends on chosen model |
| Public API | ||
| Routes models | ||
| Changes / 30d | 0 | 19 |
| Origin | Global | Global |
| Capabilities | Voice and chat agents, Agent OS, Brand persona control, Supervisor tooling, Outcome analytics, Horizon (Long-horizon agents), Ghostwriter (Agent-building agent), Agent Studio 2.0 | DOM-aware agent loop, Playwright control, Structured output, Cloud runners, Session recording, Fully Hosted Web Agents, Stealth Browsers, Browser Harness |
Browser Use
Open-source library that gives LLM agents reliable browser control.
Full Browser Use record →