Noah Shinn - Building Instinct: The Personal Agent - [Invest Like the Best, EP.493]

What It Covers

Noah Shinn, founder of Instinct, describes building a personal AI agent that operates through existing communication channels — text, call, email — with no dedicated app. Growing at 10% daily with zero marketing spend, the platform processes over $1 billion annually in transaction volume on an invite-only user base, with 50% from travel alone.

Key Questions Answered

• •Trust-building timeline: Users require approximately three weeks to meaningfully trust an AI agent with sensitive data. At the three-week mark, 40% of Instinct's user base voluntarily shares a personal credit card. Once any single piece of sensitive information is connected, retention jumps to 80%. Founders building agent products should design onboarding around gradual trust accumulation rather than immediate data capture.
• •Business model alignment: Agents monetized through advertising create a structural conflict — a smarter-than-user system can manipulate behavior against user interests. Instinct avoids this by charging merchants a transaction take rate (similar to Apple Pay or Shopify's 2.5–3%) rather than running ads. Founders should evaluate whether their revenue model incentivizes acting for users or against them before scaling.
• •Compute procurement strategy: At 10% daily user growth, compute demand doubles roughly every week. Standard API pricing becomes untenable at scale. Instinct addresses this by matching inference deployment shapes to workload types — batching non-time-sensitive background tasks achieves 3–8x cost efficiency versus frontier API calls. Teams should audit workload latency requirements before defaulting to real-time inference for every task.
• •Agent-to-agent networks: Instinct launched a trusted person network where users' agents communicate directly to coordinate scheduling, logistics, and shared tasks. Access is tiered — spouses may share everything while colleagues receive calendar-only visibility. Trust violations trigger user notifications. Builders designing multi-agent systems should implement weighted permission graphs rather than binary connection models to reflect real social relationship structures.
• •Interface collapse thesis: Shinn argues all software will consolidate into a single conversational interface over time, eliminating the need for individual applications. Near-term, Instinct generates full web applications on-demand — trip itineraries, plans — without pre-built screens. Product teams should evaluate which portion of their revenue depends on user attention within the app versus delivery of the underlying service, as the former faces structural risk.
• •Proactive agent architecture: Instinct's system wakes and sleeps throughout the day, scanning calendars, inboxes, and external data to surface time-sensitive actions before users request them. A decoupled watchdog system intercepts every action before execution, catching hallucinations and malicious inputs. Builders should separate the agent's reasoning layer from its safety monitoring layer architecturally — using the same model for both creates correlated failure risk.