Sierra

Sierra is an AI customer-service company building enterprise agents that resolve real customer issues end-to-end, including voice interactions over realtime models.

Key facts

• Type: AI customer-service agent company
• Domain: Enterprise customer service, voice agents, workflow automation
• Mentioned in wiki through: OpenAI's GPT Realtime 2 Build Hour customer spotlight ^[src-083]
• Production focus: Sierra emphasizes task completion, allowed actions, policy grounding, workflow definition, and safe tool use rather than simply making an agent sound human ^[src-083].
• Realtime model use: Sierra says GPT Realtime 2 improves latency, turn-taking, reasoning, and speech quality for voice customer-service agents ^[src-083].
• Measured impact: Sierra reported initial testing with calls roughly 30% faster at P50 and up to 200% faster at P90 compared with a cascaded voice stack, based on its internal evaluation ^[src-083].

Production view

Sierra treats a realtime speech model as one component inside a larger Production Voice Agent Harness. The surrounding system defines customer-specific workflows, allowed tools, brand language, guardrails, grounding, VAD behavior, tracing, redaction, and payment-safe flows ^[src-083].

Related

• See also: OpenAI, GPT Realtime 2
• Concepts: Voice Agents, Live Voice Models, Production Voice Agent Harness, LLM Observability, Agent Security Boundaries

Source references

• ^[src-083] OpenAI – "Build Hour: GPT-Realtime-2" (2026-05-13)