Sierra

Sierra is an enterprise AI agent platform that lets large consumer brands put a conversational agent in front of their customers to answer questions and finish tasks on their behalf. Co-founded by former Salesforce co-CEO Bret Taylor and former Google executive Clay Bavor, it is built for companies that need an agent to change a flight, troubleshoot a modem or update a mortgage application, not just recite help center articles. Its pitch is one agent with one brand voice that works the same way on the phone, in chat and over messaging.

What is Sierra used for?

Sierra is mainly used to automate high-volume customer service conversations while keeping the company's policies, tone and guardrails in place. Teams give it their standard operating procedures and system access, then measure and tune it over time.

• Building agents from uploaded SOPs, call transcripts or plain-English goals with Ghostwriter
• Running the same agent across web chat, SMS, WhatsApp, email, phone calls and ChatGPT
• Connecting to order, account and billing systems so the agent can make changes, not just answer
• Reviewing conversations with Explorer and flagging ones that need attention with Monitors
• Testing changes with multivariate Experiments before rolling them out widely
• Adding memory and customer context so returning customers do not repeat themselves

Who Sierra is best for

Sierra suits large enterprises with millions of customer contacts a year, an existing contact center and the internal capacity to run a serious deployment. Its named customers include brands in mortgage lending, satellite radio, ride hailing and telecom. A small online store or a startup with a few hundred tickets a month will find it oversized; a self-serve tool is a better fit there.

Sierra pricing

Sierra does not publish a price list. Its site describes outcome-based pricing, meaning customers pay for completed work such as a resolved conversation rather than for seats or raw message volume. There is no free plan or self-serve trial, so the only route in is a sales conversation where volume, channels and integrations are scoped. This reflects what the site showed as of October 2026.

Limitations to keep in mind

• No public pricing, so budgeting requires a sales process before you can compare costs
• Deployments depend on integrating your own systems, which takes engineering and security review time
• Outcome definitions need careful agreement up front, or billing disputes can follow
• Not designed for small businesses that want to sign up and launch in an afternoon

Sierra vs alternatives

Robylon covers similar ground, with AI agents that act on requests across email, chat, phone and WhatsApp, and may be easier to start with for mid-sized companies. Relevance AI is the better choice if you want a general agent-building platform that also handles sales and operations work, not only customer service. HubSpot Breeze makes sense when your support team already lives in HubSpot and you want agents built on that CRM data. Sierra wins when you are a large brand that needs one agent across voice and digital channels with strict compliance requirements and pricing tied to results.

Tips for getting started with Sierra

Start by picking two or three high-volume, well-documented journeys, such as order status or address changes, rather than trying to automate everything at launch. Collect your current SOPs and a sample of real transcripts before the first workshop, since Ghostwriter builds agents from that material. Agree on exactly what counts as a billable outcome during contracting. Finally, set up Monitors early so your team reviews edge cases from the first week.

Sierra FAQ

Is Sierra free?

No. Sierra has no free plan or self-serve trial, and pricing is outcome based and quoted by its sales team.

What is Sierra used for?

Sierra is used by large companies to run AI customer service agents that answer questions and complete tasks across chat, voice, SMS, WhatsApp and email.

Does Sierra support phone calls?

Yes. The same Sierra agent can handle voice calls as well as digital channels, so customers get consistent answers on the phone and in chat.

What is the best alternative to Sierra?

Robylon is a close alternative for multichannel AI support agents, while Relevance AI suits teams that want a broader agent platform for several departments.