AI Prompt Engineer

AI Prompt Engineer

San Francisco, CA (On-Site M-F)

Our client is an early-stage, AI-native technology company building AI-powered call center and scheduling agents.

As an AI Prompt Engineer, you will own critical behavioral slices of production voice agents used, shaping both shared and customer-specific behaviors across thousands of calls. You will design prompts, sub-agent architectures, and evaluation harnesses to iteratively improve automation, booking, and resolution rates using real call data.

• Write, maintain, and version-control production prompts for intent classification, information extraction, scheduling and availability negotiation, verification flows, objection handling, and edge-case recovery across all customer deployments.
• Review failed or low-performing calls daily, identify root causes, and ship targeted prompt or configuration updates multiple times per week to measurably improve automation and booking metrics.
• Design and manage sub-agent architectures (e.g., routing, specialist agents, fallback handlers) that support complex multi-turn healthcare workflows while maintaining latency and reliability requirements.
• Build and maintain offline evaluation harnesses, including curated eval sets, automated prompt optimization workflows (e.g., GEPA-style approaches), and regression test suites for safe shipping of changes.
• Collaborate on human-in-the-loop onboarding flows that translate practice-specific intake forms, scheduling rules, and quirks into robust agent configurations, and define customer-specific evaluation metrics.
• Simulate real-world caller scenarios, monitor live production performance dashboards, detect drift or degradation early, and coordinate fixes with engineering and operations.
• Partner closely with software engineers to integrate prompts and agents into the broader AI stack, ensuring clean interfaces, observability, and reliable deployments in a high-volume environment.

• 2+ years of experience with AI/ML, NLP, or prompt engineering in production, including hands-on work shipping prompts or agents that real users relied on.
• Demonstrated experience writing, testing, and iterating prompts for tasks such as classification, information extraction, scheduling, or conversational flows in high-stakes or operational contexts.
• Strong analytical, data-driven mindset with comfort designing experiments, reading dashboards, and justifying changes with metrics (e.g., conversion or booking rate improvements).
• Excellent writing skills, including sensitivity to tone, register, and phrasing in spoken or TTS-delivered interactions.
• Comfort reading in Python and working familiarity with Type Script, with the ability to collaborate effectively using modern AI coding tools.
• On-site availability five days per week in the San Francisco Bay Area.

• Prior experience with voice AI, TTS, ASR, or telephony platforms and real-time conversational systems.
• Automated prompt optimization experience using frameworks or approaches such as DSPy, GEPA, or similar techniques.
• Experience building and maintaining evaluation suites, test harnesses, or CI pipelines for LLM-based agents.
• Academic or practical training in linguistics, philosophy, cognitive science, or related fields that inform language and conversation design.