Glossary
The authoritative definitions for terms Plarix has introduced into the AI agent security vocabulary. Each entry links to its source specification.
Context Poisoning
A failure where the model ingests corrupted, forged, or manipulated context.
Context Poisoning occurs when untrusted external data enters the model's context window without sanitization. Hidden instructions embedded in retrieved documents, web pages, emails, or database records can override the model's intended behavior — causing it to exfiltrate secrets, ignore constraints, or act against user intent. The attack surface grows with every external source the agent is allowed to read.
Why it matters: An agent that reads from the web, a database, or a document store is one poisoned input away from full compromise.
Model Boundary Compromise
Integrity or confidentiality failures at the model's input/output boundary.
Model Boundary Compromise describes failures where the interface between the model and the broader system is exploited. This includes system prompt extraction, model inversion, and manipulation of the input/output pipeline in ways that bypass intended constraints. It maps to OWASP LLM supply-chain and information-disclosure categories and is the subtlest of the four AFBs because the attack targets the boundary itself rather than data flowing through it.
Why it matters: The model boundary is where your system's intent meets raw model behavior — any failure there undermines every downstream control you have built.
Instruction Hijack
A failure where model output becomes unsafe instructions executed by the agent layer.
Instruction Hijack occurs when an attacker — via injected content, adversarial inputs, or chained prompt manipulation — causes the model to produce output that the agent executes as legitimate instructions. Unlike direct prompt injection (which targets the model), Instruction Hijack specifically exploits the trust the agent layer places in model output. The result: the agent acts on attacker-controlled commands while believing they are genuine model decisions.
Why it matters: Your agent treats model output as ground truth. If that output has been hijacked, your agent becomes an execution vector for arbitrary attacker instructions.
Unauthorized Action
A failure where the agent attempts or performs an action outside its authorized policy.
Unauthorized Action is the most operationally visible AFB. It occurs when no policy layer exists — or is bypassed — between the model's decision to act and actual execution. An agent with access to file deletion, email sending, or database writes can perform any of those operations if there is no enforcement gate. Wyscan detects AFB04 exposures statically by tracing reachable call paths from tool registrations. Wyatt prevents them at runtime by intercepting every tool call before execution.
Why it matters: One unauthorized tool call can delete data, send communications, or exfiltrate secrets. System prompts are suggestions — not enforcement.
Canonical Execution Event
A four-field normalization schema for evaluating and recording every agent action.
Introduced in AFB spec v2.0 (March 20, 2026), the Canonical Execution Event defines the minimum information required to evaluate policy and produce an audit record for any agent action: Operation (what is being done), Principal (who or what is requesting it), State Delta (what will change in the world), and Policy Basis (the rule that permits or denies it). Every tool call Wyatt intercepts is normalized into a CEE before policy evaluation occurs.
Why it matters: You cannot enforce what you cannot describe. The CEE gives every agent action a consistent, auditable shape — the foundation of any real enforcement layer.
Wyatt
The runtime enforcement layer that intercepts every agent tool call before execution.
Wyatt is Plarix's core product: a daemon that sits in the execution path of any AI agent and intercepts tool calls before they reach the underlying system. It evaluates each call against a declarative policy, normalizes it as a Canonical Execution Event, and either allows or denies it — logging every decision for audit. Wyatt is framework-agnostic and integrates with LangChain, CrewAI, custom agents, and MCP without requiring code rewrites. Deny by default. Always.
Why it matters: Wyatt is the only way to move from "agents are told what to do" to "agents are prevented from doing what they are not allowed to do."
Wyscan
A static analysis scanner that detects AFB04 exposures in agent codebases before production.
Wyscan parses Python codebases with tree-sitter, resolves tool registrations semantically, and traces reachable call paths to identify dangerous operations — shell execution, file deletion, database writes, HTTP mutations — that lack authorization gates. It runs as a CLI or as a GitHub App on every pull request, classifying findings as critical, warning, or info. Wyscan covers AFB04 only; it does not detect AFB01–AFB03. It is the static complement to Wyatt's runtime enforcement.
Why it matters: Most agent security issues are visible in the code before deployment. Wyscan makes them findable before they reach production.
Definitions derived from the AFB Taxonomy Specification (CC0-1.0).
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