Principal Autonomous Agent Fleet Architect

STN, Inc.; San Francisco (CA); On-site; USD 180,000 - 260,000; Full time

Job summary

Horizon AI seeks a Principal to Distinguished (MTS 5–6) to own the reasoning layer for a fleet of autonomous agents operating on STN’s GPU infrastructure in SF. You will design how agents diagnose problems, decide actions, and explain decisions, while gating actions with an evidence-based framework.

You will build evaluation harnesses, set autonomy SLOs with the Chief Architect, and shape the governance around tool use, escalation, and write permissions across distributed systems.

Qualifications

• Built and shipped LLM-based agentic systems in production, including failure modes and debugging.
• Strong opinions about evaluation and measurable success criteria in autonomous systems.
• Experience with tool and function calling at scale, and with LLM tracing and online evaluation.

Responsibilities

• Own the reasoning layer: dozens of agents that diagnose fleet issues and decide actions.
• Own the gating mechanism to prove agent decisions before action.
• Define and implement evaluation harnesses for agent behaviour in real incidents.

Skills

LLM-based agent systems

Python distributed systems

Multi-agent orchestration

LLM tracing

Job description

Horizon AI seeks a Principal to Distinguished (MTS 5–6) to own the reasoning layer for a fleet of autonomous agents operating on STN’s GPU infrastructure in SF. You will design how agents diagnose problems, decide actions, and explain decisions, while gating actions with an evidence-based framework.

You will build evaluation harnesses, set autonomy SLOs with the Chief Architect, and shape the governance around tool use, escalation, and write permissions across distributed systems.