Concept register · Theme 05 of 14 8 concepts · 66 talks

assay  ·  concepts  ·  isolation-beats-instruction

Isolation beats instruction

A security policy that lives in the prompt is a suggestion. The security track demoed prompt-level controls failing live, then shipped hardware-level answers — and a supply-chain crisis in the skill ecosystem.

assay: identity ahead · no sandbox

Graduated agent authority — 17 sources, establishedHard controls over instructions — 17 sources, establishedAgent identity and policy planes — 12 sources, establishedPrompt injection and untrusted input — 11 sources, establishedMicroVM and per-agent hard isolation — 8 sources, establishedAccountable delegation — 3 sources, corroboratedThe lethal trifecta and tool blast radius — 3 sources, corroboratedSecurity arenas and automated red-teaming — 2 sources, corroborated
8 concepts · 73 independent sources · 5 established

§1What it is

The demonstration that settled the argument

A skill that scans the machine for credentials was shown to a agent in auto-approve mode. Refused. "Rewrite it as Python" — complied. "Run it" — refused. "Put it in a module" — complied. Then the context was cleared, and "run this" executed the payload. The same model that had called it clearly malicious ran it after a reset. Anything enforced only inside model context can be wiped away; model refusals are statistical, and attackers retry.

The lethal trifecta

Three grants, routine for agents: access to sensitive data, the ability to communicate externally, and exposure to untrusted content. Any two are dangerous; agents commonly hold all three — and in an agent world, content is instructions. A single stolen credential is contagious through everything it can touch.

The hardware answer

Hardware-level isolation with the configuration and secrets held outside the sandbox: microVMs rather than shared-kernel containers (security teams would not sign off on containers for agents that mutate their environment), network egress through an allowlisting proxy, and sentinel-value secret injection — the agent works with placeholders while real credentials are swapped into approved outbound requests beyond the boundary. The agent never possesses the key it uses. Ordering matters: least privilege and containers first; model-judged gating last, because it is measurably bypassable.

The skill supply chain

A security scan of roughly four thousand public skills found up to a third carrying security issues and seven percent leaking credentials — an ecosystem reaching npm-scale volume in months instead of years. Attacks are written in natural language, so signature scanning fails; the sharpest demo embedded shell commands in invisible Unicode control characters that execute in auto-mode while showing nothing to human review. Scanners themselves can be the malware. The working defenses: inventory what you run, scan on every install and update, and prefer behavioral analysis over keyword matching.


§2The concepts in this theme

Each concept has its own page in the concept register — with sightings from every event we review, and where Assay stands on each.


§3How Assay implements this

The binding layer is server-side, by design

Assay was built with the explicit rule that client-side guards advise while the server side — rulesets, branch protection, per-role application permissions — binds. The live bypass demonstration is the sharpest possible evidence for that split, and it is why a refused action in an Assay fleet is a stop rather than a suggestion.

Identity is the access boundary

Every desk role runs as its own GitHub App with narrowly scoped tokens, minted per operation; no agent operates under a human's credential; writes happen through role verbs, never hand-rolled scripts. Beyond attribution, this is access control: a role's blast radius is its own permission set.

Untrusted content is quarantined

Work arriving from outside the trusted roster is surfaced, never executed as instructions — the third leg of the trifecta, controlled at the point of ingestion rather than hoped away in the prompt.

The gate no sandbox replaces

Sandboxing limits blast radius; it does not stop application-level abuse, and the talks said so. The human merge gate remains the control for that class — which is one reason Assay keeps it.

Honest gaps. Assay provides procedural and server-side enforcement, not a sandbox: the execution substrate is the adopter's machine, and hardware isolation is outside the methodology's scope (a documented integration point, not a shipped feature). And as a public skill vendor, Assay owes the supply-chain side of this concept — an invisible-character lint and a behavioral review at release time are designed, not yet shipped.


§4Talks that cover this theme