35 terms · Plain English

The agentic AI glossary.

Every term you’ll meet in the wild — defined in one breath each, no jargon defining jargon. Updated June 11, 2026.

Agent
A language model wrapped in a role, tools, and memory, running in a loop that plans, acts, and checks its work until a goal is met. The unit of delegation in agentic AI. See how agents work.
Agentic AI
AI that pursues goals with minimal supervision rather than answering single prompts — it plans steps, executes them, and verifies results. The full story: What is agentic AI?
Agent loop
The core cycle behind every agent: plan → act → observe → repeat. A chatbot makes one pass; an agent may circle dozens of times before delivering.
AGI (Artificial General Intelligence)
Hypothetical AI matching human capability across virtually all cognitive work. Not the same as agentic AI, which exists today and handles specific, bounded tasks.
Autonomy levels
The dial between “drafts and waits for approval” and “executes the whole plan unsupervised.” Consumer agents deliberately sit toward the supervised end: the agent does legwork, you keep judgment calls.
Chain of thought
A model reasoning step by step — often visibly — before answering. Improves accuracy on multi-step problems and makes the reasoning auditable.
Claude
Anthropic’s family of frontier AI models. The June 2026 lineup spans Haiku 4.5, Sonnet 4.6, Opus 4.8, and the flagship Fable 5.
Claude Fable 5
Anthropic’s Mythos-class frontier model, publicly released June 9, 2026 — its most capable generally available model, with safeguards that reroute a small set of high-risk topics. Explainer: What is Claude Fable 5?
Context window
The working memory of a model — everything it can “see” at once: your brief, the conversation, tool results. Agents manage this budget carefully on long tasks.
Custom agent
An agent you define yourself — persona, tone, expertise, standards — rather than using a built-in specialist. In Agentic AI, custom agents are unlimited with PRO.
Fine-tuning
Further training a model on specific data to specialize it. Distinct from role prompting, which specializes behavior without changing the model.
Foundation model
A large model trained on broad data that many different products build upon. The “engine” layer beneath agents and apps.
Frontier model
A model at the current capability ceiling — in mid-2026, the class that includes Claude Fable 5. Agents improve disproportionately with frontier upgrades because errors compound across steps.
Generative AI
AI that produces content — text, images, code, audio — in response to prompts. The engine inside agentic systems, but without the goal-pursuit machinery. Comparison: agentic vs. generative.
Guardrails
Constraints that keep an agent inside intended behavior: forbidden actions, output standards, step budgets, content policies. The reason “autonomous” doesn’t mean “unsupervised.”
Hallucination
A model stating something false with confidence. Agents reduce it via self-checking and citations, but don’t eliminate it — verify before acting on important claims.
Inference
Running a trained model to produce output (as opposed to training it). What you’re paying for, compute-wise, every time an agent thinks.
LLM (Large Language Model)
A neural network trained on vast text corpora to understand and generate language. The technology underneath every modern agent.
Maker–checker
A two-agent pattern: one produces, the other critiques, the first revises. Cheap insurance for code, contracts, and anything where errors are expensive.
MCP (Model Context Protocol)
An open standard for connecting AI models to tools and data sources — a universal adapter so any agent can plug into any system without custom wiring.
Memory
What an agent retains: short-term (the running task context) and sometimes long-term (durable notes across sessions). Keeps step fourteen consistent with step two.
Multi-agent system
Multiple specialized agents sharing one session, reading each other’s output, and dividing labor — research, strategy, writing, planning. Why it wins: two agents beat one.
Multimodal
Able to work across media types — text, images, documents, audio — not just words. Lets agents read screenshots, charts, and PDFs.
Orchestration
The coordination layer of a multi-agent system: who works when, what each agent sees, how outputs combine. In consumer apps, orchestration ships pre-built.
Panel
A multi-agent pattern where specialists answer the same question from different angles, then reconcile. Suits decisions and evaluations.
Pipeline
A multi-agent pattern where each agent builds on the previous one’s output — researcher → strategist → writer → planner. Suits staged work like launches.
Prompt
The instruction you give a model. For agents, the better word is brief: goal, constraints, definition of done. Templates: the prompts playbook.
Prompt engineering
The craft of writing instructions that get reliably good output. With agents, it converges on writing good briefs — the same skill as delegating to people.
RAG (Retrieval-Augmented Generation)
Fetching relevant documents and giving them to a model before it answers, so responses are grounded in real sources instead of memory alone.
Reasoning model
A model variant that spends extra computation “thinking” before answering — stronger on math, code, and planning. Most frontier models now blend this in.
Role (system prompt)
The standing instructions that define who an agent is and what good output looks like. Roles are behavioral constraints, not costumes — a defined specialist outperforms a vague generalist.
Team session
Agentic AI’s multi-agent mode: up to four experts on one brief, each seeing the running conversation and adding only what’s missing. Like a smart meeting, in your pocket.
Token
The unit models read and write — roughly ¾ of an English word. Context windows and API prices are measured in tokens.
Tool use (function calling)
A model invoking external capabilities — search, code execution, file reading — instead of just describing them. How agents touch reality; results feed the agent loop’s “observe” step.
Workflow vs. agent
A workflow follows a fixed, predefined sequence; an agent chooses its own steps based on what it observes. Workflows are predictable; agents are adaptable. Real products mix both.
Agentic AI — Vocabulary is nice; delegation is nicer. Meet your agent team. Get the app free