Glossary · 25 terms
Say what you mean.
The terms used across our tools and papers, in plain words. Each one links to the paper or tool it comes from.
General
- AI Reliability Engineering
The practice of making AI agents testable, bounded and auditable: memory with sources, contracts that are checked, tests that account for randomness, loops that end on evidence and skills checked before they run.
Memory
Memory hub- Memory poisoning
When one compromised or careless agent writes false facts into a memory store that other agents share, so every agent that recalls from it is misled.
- Writer trust
A per-source trust score, modelled as a Bayesian posterior and updated by downstream outcomes, so a writer whose facts keep failing verification loses influence over retrieval.
- Zero-LLM retrieval
Memory retrieval that ranks results by computation, such as distances on a statistical manifold, instead of calling a language model in the hot path.
- Multi-channel retrieval
Searching memory through several independent channels at once and fusing their results by reranking, so no single index decides what is recalled.
- Memory decay
Deliberate forgetting with decay curves and consolidation, so old facts stop crowding out current ones as a memory store grows.
- Provenance
A record of where a remembered fact came from, kept alongside it so any recall can be traced back to its source.
Evaluation
Evaluation hub- Stochastic verdict
A test result reached over repeated runs of a non-deterministic agent, judging the distribution of outcomes instead of a single sample.
- Non-deterministic regression testing
Checking that a change did not make an agent worse when its output differs every run, so comparing against a golden file is not possible.
Loops
Loops hub- Bounded loop
An agent loop with proved termination under a global repair budget, an enforced spend ceiling, and completion only on an independent gate verdict.
- Gate verdict
The pass or fail result of an independent check that decides whether a loop step is done, instead of the agent's own claim.
- Vacuous gate
A check that looks sound but passes any input, for example a test that asserts nothing. One of two ways a gate passes anything.
- Self-attestation
When the agent being checked also produces the evidence its check relies on, so the gate only confirms what the agent said. The second way a gate passes anything.
- Spend ceiling
A cost limit enforced inside an attempt, while it runs, rather than checked only between attempts.
- Hash-chained ledger
An append-only log of loop iterations and gate verdicts where each entry carries the hash of the one before, so the history cannot be edited unnoticed.
- Agent topology
The shape in which agents are connected and run, such as sequential, parallel, hierarchical, debate or mesh, each with defined execution semantics.
- Degradation ladder
Tiers of fallback behaviour that keep a multi-agent system answering when parts of it fail: autonomous swarm, deterministic graph, single agent, then a human in the loop.
Security
Security hub- Agent skill
A packaged capability an agent can install and run, executed with the agent's own authority.
- Skill supply chain
The path a skill takes from author to registry to your agent. A registry with no review gate makes every install a trust decision.
- Skill bill of materials
An inventory of what a skill contains and depends on, generated so it can be reviewed before the skill executes.
Contracts
Contracts hub- Behavioural contract
Design-by-contract applied to an autonomous agent: formal, runtime-enforceable rules about what it must and must not do, with recovery when it drifts.
- Contract components (P, I, G, R)
The four parts of an agent behavioural contract: preconditions that must hold before the agent acts, invariants that must hold throughout, governance policies, and recovery mechanisms for when a constraint is broken.
- Failure independence assumption
The common but rarely tested assumption that agents in a system fail independently. Measured dependence is strongly positive, so bounds built on it understate joint failure.
- Contract proxy
An HTTP proxy between an agent and its model provider that enforces contract rules, such as budgets and tool allowlists, with no change to the agent's code.
- Typed decision
A bounded choice, such as which tool or skill to use, answered from a fixed set of options with a confidence and a local receipt. The host keeps execution authority.