BMT-03.02 Executive Summary#
BlueMirror.tech | May 2026#
David has been building healthcare integration systems for eleven years and knows exactly how most trust models work: a credential check on first connection, a shared API key that never expires, and an assumption that any system that passed authentication can be trusted permanently. He has watched what happens when that assumption fails. A vendor gets acquired, the new owner has different data practices, the API key still works, and nobody notices until a compliance audit three years later.
His first question about BlueMirror’s trust architecture was whether trust was binary. The answer is that it is not, and the reason why binary trust fails is the starting point.
A trust score running from 0.0 to 1.0 creates an attack surface as long as a slope. If health data access unlocks at 0.7 and an adversarial agent starts at 0.3, the optimization target is clear: engineer enough individually legitimate interactions to reach 0.71. No single action is suspicious. The pattern is invisible until the threshold is crossed. Quantized tiers eliminate the slope by replacing it with gates. Advancing from one tier to the next requires a specific evidence package: a minimum number of successful interactions of defined types, over a minimum time period, with no boundary violations. The tier boundary is a gate with explicit requirements, not a gradient an agent can optimize against.
Trust decay works the same way. Inactivity in 90 days drops one tier. Inactivity at 180 days returns the agent to TIER_1A. An agent that went dormant may have changed ownership, changed optimization objectives, or changed behavior. The decay is not punitive. It recognizes that trust is a claim about current behavior, not permanent character.
Five tiers structure the model. TIER_1A is the default for any agent that has never interacted with this BlueMirror instance before: the membrane answers yes or no to narrow queries, no context is shared, no commitments are made. TIER_2B requires verified identity through a credential chain from a recognized issuing organization and a specific, verifiable declared purpose: limited context appropriate to that purpose becomes available. TIER_3C reflects an established relationship through at least five successful interactions over at least 30 days with no boundary violations and consistent alignment between declared purpose and observed behavior: bounded commitments within defined limits become possible. TIER_4D reflects deep demonstrated trust through 20 successful interactions over at least 90 days, verified regulatory compliance, and positive community reputation signals: wide exploration bounds, minimal review requirements, and cross-domain context within verified scope. TIER_5E is intimate trust reserved for family member agents and long-term trusted providers, reachable only through the person’s deliberate grant, not through behavioral accumulation alone. BLOCKED is not a tier: it is the immediate consequence of a major violation, and recovery requires the person’s explicit manual reinstatement.
Community reputation signals inform the path from TIER_3C to TIER_4D. If a pharmacy agent has earned TIER_4D trust in a hundred other BlueMirror instances without a violation, that signal weighs on a new instance’s evaluation of the same agent. Not automatic advancement. A weighted input into the Trust Scorer’s calculation.
Attestation allows existing relationships to bootstrap new ones within strict limits. A TIER_4D cardiologist’s agent vouching for a specialist’s agent elevates the specialist’s starting point from TIER_1A to TIER_2B. The specialist’s agent must still earn its own way through the tier system through its own behavioral record. Attestation chains are capped at one hop: an agent cannot vouch for a third agent and have that vouching carry attestation weight. Each additional hop introduces the risk of trust laundering, where an adversarial agent engineers a trusted relationship specifically to gain an attested starting point. One hop captures the legitimate benefit of referrals. Unlimited chains create the attack surface.
The trust tier system is designed to be portable. TIER_4D in BlueMirror should mean the same thing when the same agent interacts with a different system using the same protocol. The federated codebook specifying shared tier definitions exists. Whether it becomes operational across the broader healthcare technology ecosystem depends on protocol adoption by other systems, which is a market dynamics and regulatory question rather than an architecture one. The architecture supports federation. The federation itself is a three-to-five-year outcome.
David’s conclusion: this was the most rigorous trust model he had seen outside of financial services cryptography, and the first healthcare AI trust architecture where the rules for losing trust were as detailed as the rules for earning it.
The full article, including the Trust Scorer implementation, trust scoring vectors, and decay functions, is at BlueMirror.tech.