The Harmonic Theory of Agentic Systems: How Multi-Session AI Programs Drift, Fail, and Return to Coherence

By Danny Argudin

Agentic AI programs don't fail the way most practitioners expect.

They don't crash. They don't produce error messages. They keep running - generating plausible output, writing coherent-looking reports, making locally reasonable decisions - while quietly drifting from the program's original intent.

The Harmonic Theory of Agentic Systems names this failure: drift. And it gives practitioners the vocabulary, the instruments, and the governance architecture to detect it, measure it, and reverse it before it becomes a recovery event.

The framework is drawn from signal processing. Agentic programs, like physical systems, have natural frequencies - characteristic rhythms at which coherence builds and decays. These rhythms operate at three timescales simultaneously: within a single session, across multiple sessions over days and weeks, and at the quarterly arc where strategic direction silently rotates. Governing each requires different instruments. Managing them as one produces none.

This is a practitioner book. It was written inside the multi-session agentic program it describes - a program that, at times, drifted, and whose recovery from drift provided the clearest evidence about how the phenomenon works.

What you will find here:
- The three natural frequency bands of agentic programs and why each requires distinct governance
- The 98-minute session law, derived from architectural constants, not intuition
- The antinode principle: why checkpoint timing matters more than checkpoint frequency
- The DC component failure - the silent drift that looks like progress until it doesn't
- Seven anti-patterns, each with a physics diagnosis and a structural remedy
- A catalog of recovery paths from every class of coherence failure

By Chapter 3, you have the vocabulary. By Chapter 6, you understand why programs drift at three distinct timescales. By Chapter 11, you have seen the worst case - and what recovery looks like.

For practitioners building AI programs that run for more than one session. For technical leads who need to govern without micromanaging. For anyone who has watched an agentic system lose the thread - and wants to know exactly why it happened.

The proof is in the physics. The physics is in the framework. The framework is in the work.

• Format: Paperback
• Language: English
• ISBN: B0H23BP8YM
• ISBN13: 9798197171498
• Release Date: May 2026
• Publisher: Independently published
• Length: 245 Pages
• Weight: 0.74 lbs.
• Dimensions: 9.0" x 0.6" x 6.0"