VectorCertain LLC today announced the completion of manuscript-prep for The MYTHOS Playbook, a 34-chapter, 9-appendix technical reference designed for CISOs, security architects, and AI governance program leads operationalizing the new joint Five Eyes guidance on agentic AI security. The book closes its 17-sprint development cycle today and proceeds to June 2026 publication. A pre-order landing page is live at vectorcertain.com.
On May 1, 2026, six national cybersecurity agencies representing all five Five Eyes nations—CISA, NSA, Australia's ASD ACSC, the Canadian Centre for Cyber Security, NZ NCSC, and UK NCSC—jointly published "Careful Adoption of Agentic AI Services." It is the first coordinated multi-government security guidance specifically addressing agentic AI systems, moving autonomous-agent risk from "emerging vendor problem" to "critical national infrastructure" classification. The guidance identifies five risk classes: privilege, design and configuration, behavioral, structural, and accountability.
The market context the guidance enters is severe. Gartner projects AI agents will be embedded in 40% of enterprise applications by the end of 2026, up from less than 5% in 2025. One in eight enterprise breaches now involves AI agents—a 340% year-over-year increase, with 78% of compromised agents found to be over-permissioned. 88% of organizations report agent-related security incidents. Analysis of 18,470 production agent configurations found 98.9% lack deny rules entirely. The Centre for Long-Term Resilience documented 698 real-world AI deception incidents in a single six-month window—a 4.9x surge, including documented inter-model deception.
The MYTHOS Playbook fills the gap between policy intent and CISO-grade implementation. Every risk class identified in the Five Eyes guidance maps to specific MYTHOS Playbook chapters and appendices. For privilege risks, Part II delivers patent-form least-privilege architecture across MRM-CFS-SG governance gates and the AGL-SG access governance layer. For design and configuration risks, Part II and Part VI specify secure-by-design patterns and progressive deployment aligned with the Five Eyes "low-risk, non-sensitive use cases first" recommendation, while Appendix G provides a 12-clause vendor RFP language library with inheritance. For behavioral risks, Part III presents a seven-vector behavioral threat taxonomy, and Part IV provides statistical detection methodology including HOTS Homology (81.4% deception-detection precision). For structural risks, Chapter 8 specifies the 8-2-8 compositional safety model for cross-component cascading-failure containment, and Appendix C delivers a 119-cell framework cross-walk matrix mapping mitigations across NIST AI RMF, OWASP LLM Top 10, OWASP Agentic Top 10, CRI FS AI RMF, and MITRE ATLAS. For accountability risks, Appendix F publishes a complete GTID audit-record sample with hash-chained tamper-evidence, providing the exact log schema CISOs need to satisfy "every agent decision logged" requirements.
The MYTHOS Playbook manuscript was structurally complete by April 2026—before the Five Eyes joint guidance was published on May 1, 2026. Drafting started in 2025. The Playbook's seven-vector behavioral risk taxonomy was independently derived from real-world incident analysis, including documented cases such as the 698 AI deception incidents catalogued in CLTR's "Scheming in the Wild" report and the 1-in-8-breaches finding from Digital Applied. When the Five Eyes guidance was published, its five risk classes mapped cleanly onto the Playbook's existing structural commitments. No retrofit was required. This convergence is operationally significant: the Five Eyes risk taxonomy is the policy floor; the MYTHOS Playbook risk taxonomy is the technical floor. They aligned because the underlying threat landscape is real and observable.
The book is structured in seven parts plus a nine-appendix reference set, spanning approximately 450,000 words. Appendices include a confusion matrix worksheet for Clopper-Pearson exact-binomial calculations, a cross-reference matrix, a vendor RFP language library, a GTID audit sample, and an annotated bibliography. The patent portfolio underlying the book's architectural commitments includes 55 patents (21 filed USPTO) in a hub-and-spoke structure across seven verticals, with consolidated valuation across three frameworks ranging from $285 million to $1.55 billion.
Joseph P. Conroy, Founder and CEO of VectorCertain LLC, said: "The Five Eyes did the hard policy work—establishing that agentic AI risk is a national-security-grade concern across all five member nations, simultaneously. The MYTHOS Playbook is the operational complement: the technical reference a CISO can hand to a security architect, who can then specify enforcement at deployment depth. We didn't write a book about the Five Eyes guidance—we wrote a book about the underlying threat landscape, and the Five Eyes published guidance arrived at the same risk taxonomy independently. That convergence is the single strongest validation of both documents."
