YOUR AI REFERENCE LIBRARY

AI Dictionary.

165 AI, LLM, generative AI and agent-engineering terms, from foundations to emerging developer jargon.

165terms

Combine topic filters with search. Press Esc to clear search. Each new term links to its primary reference.

165 of 165 terms to explore

BeginnerIntermediateExpert
01Beginner
PDF essentials

AI

Artificial Intelligence is the broad field of creating systems that perform tasks normally requiring human intelligence—such as pattern recognition, language understanding, or decision-making.

How it connects

First term; sets the stage.

In practice

Generative AI is a practical branch of AI focused on creating new content (text, images, code, etc.).

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 4

02Intermediate
PDF essentials

Machine Learning

A subset of AI where algorithms improve at a task through experience with data instead of explicit rule-based programming.

How it connects

Machine Learning is how most modern AI - including generative systems - actually learns.

In practice

Generative AI models are built using Machine Learning techniques.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 4

03Intermediate
PDF essentials

Neural Network

A layered collection of mathematical “neurons” that learn to map inputs to outputs by adjusting weights during training—loosely inspired by the brain.

How it connects

Neural Networks are the dominant Machine Learning architecture powering today’s AI.

In practice

All mainstream generative models (e.g., GPT, DALL·E) are large neural networks.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 4

04Expert
PDF essentials

Deep Learning

A Neural Network with many layers (“deep”) that can automatically learn complex patterns in data.

How it connects

Deep Learning extends Neural Networks to substantial depth, enabling breakthroughs in language and vision.

In practice

Generative models rely on deep architectures to capture the nuances needed to create fluent text or realistic images.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 4

05Intermediate
PDF essentials

Data Corpus

A large, curated collection of text, images, audio, or other data used to teach models about the world.

How it connects

Deep Learning’s power grows with bigger, richer corpora.

In practice

The breadth and quality of a corpus determine how creative, factual, or biased a generative model may be.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 5

06Expert
PDF essentials

Feature

An individual measurable property or signal extracted from raw data to help a model learn (e.g., word position, pixel intensity).

How it connects

Features are distilled from a Data Corpus before or during training.

In practice

Modern generative models often learn to create their own features internally, reducing manual engineering.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 5

07Beginner
PDF essentials

Token

The smallest unit a language model processes—commonly a word, sub-word, or even character.

How it connects

Tokens are standardized features for text data.

In practice

Text generators predict one token at a time to compose sentences.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 5

08Intermediate
PDF essentials

Vocabulary

The full set of tokens a model recognizes and can output.

How it connects

Tokens collectively form the model’s vocabulary.

In practice

Vocabulary size affects fluency, specificity, and model size.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 5

09Intermediate
PDF essentials

Embeddings

Dense numerical vectors representing tokens, images, or other items so that semantic similarity is captured as geometric closeness.

How it connects

Each token in the vocabulary maps to an embedding.

In practice

Embeddings enable models to reason about meaning and relationships, crucial for coherent generation.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 5

10Intermediate
PDF essentials

Vector Space

The multi-dimensional mathematical space in which embeddings reside; distances encode similarity.

How it connects

Embeddings live and move in this Vector Space.

In practice

Manipulating vectors (e.g., arithmetic like “Paris – France + Italy ≈ Rome”) underpins many creative tasks.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 6

11Intermediate
PDF essentials

Transformer Architecture

A neural network design that uses self-attention mechanisms to process sequences in parallel, revolutionizing language and vision tasks.

How it connects

Transformers efficiently operate on sequences of embeddings in vector space.

In practice

Nearly all state-of-the-art generative language models (GPT, Gemini, Claude) are Transformers.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 6

12Intermediate
PDF essentials

Attention

A mechanism within Transformers that lets the model weigh the relevance of different tokens when producing each output.

How it connects

Attention is the core innovation that makes Transformers powerful.

In practice

By “attending” to the right context, generative models stay coherent over long passages.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 6

13Expert
PDF essentials

Pre-training

The large-scale, general training phase where a model learns from a massive corpus to predict missing tokens or pixels.

How it connects

Transformers are usually first pre-trained using attention on vast data.

In practice

Pre-training builds broad knowledge, enabling zero- or few-shot generation on new tasks.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 6

14Expert
PDF essentials

Foundational Model

A very large, Pre-trained model that can be adapted to many downstream tasks.

How it connects

Pre-training produces these versatile foundations.

In practice

Foundational models (e.g., GPT-4o) power chatbots, code assistants, and more.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 7

15Intermediate
PDF essentials

LLM (Large Language Model)

A Foundational Model specialized for text, containing billions of parameters and trained to predict the next token.

How it connects

LLMs are a prominent category of foundational models.

In practice

They are the workhorses of text generation, summarization, and conversational agents.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 7

16Beginner
PDF essentials

Generative AI

AI systems that create new content—text, images, audio, code—rather than merely analyzing existing data.

How it connects

LLMs like Gemini and Claude exemplify Generative AI for language; other modalities use similar ideas.

In practice

This is the overarching topic tying all terms together.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 7

17Beginner
PDF essentials

Context

The surrounding tokens, user instructions, or real-world situation a model considers when generating an answer.

How it connects

Generative AI quality hinges on effectively using context.

In practice

More context windows mean richer, more relevant outputs.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 7

18Beginner
PDF essentials

In-Context Learning

A model’s ability to pick up a pattern or task on the fly from examples included in the prompt—no weight updates required.

How it connects

It’s a direct outcome of how models use Context.

In practice

Enables rapid prototyping: just feed examples and the model adapts.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 7

19Beginner
PDF essentials

Prompt

The instruction and/or examples you provide to steer the model’s generation.

How it connects

Prompts are the vehicle for In-Context Learning.

In practice

Prompt engineering is a new craft for extracting high-quality output.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 8

20Intermediate
PDF essentials

Inference

The phase where a trained model generates answers in response to a prompt—essentially, runtime prediction.

How it connects

Inference executes the instructions embedded in a prompt.

In practice

Optimizing inference cost and speed is key for production systems.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 8

21Intermediate
PDF essentials

Latency

The time between submitting a prompt and receiving a model’s response.

How it connects

Latency is a user-visible aspect of Inference.

In practice

Lower latency leads to smoother chat and real-time creative tools.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 8

22Intermediate
PDF essentials

GPU

A Graphics Processing Unit—massively parallel hardware ideal for the matrix math of training and running deep models.

How it connects

GPUs help cut latency and cost during inference.

In practice

Most training and large-scale deployments rely on GPUs (or specialized accelerators).

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 8

23Expert
PDF essentials

Fine-Tuning

A targeted retraining step where a Pre-trained model is adjusted on a smaller, domain-specific dataset.

How it connects

Fine-Tuning may happen using GPUs after initial deployment.

In practice

Lets teams customize a foundational model to their brand voice or proprietary data.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 8

24Expert
PDF essentials

Parameter

A model’s learned weight value; modern LLMs have billions.

How it connects

Fine-Tuning tweaks parameters to new tasks.

In practice

Parameter count often correlates with expressiveness and memory for details.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 9

25Expert
PDF essentials

RLHF (Reinforcement Learning from Human Feedback)

A training technique where human preferences guide the model toward more helpful or less harmful outputs.

How it connects

Adjusts parameters further after Fine-Tuning.

In practice

Used to align chatbots with human expectations.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 9

26Expert
PDF essentials

Alignment

The ongoing effort to ensure an AI’s goals and behaviors match human values and intentions.

How it connects

RLHF is one method of pursuing Alignment.

In practice

Critical for safe, trustworthy generative systems in products.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 9

27Expert
PDF essentials

Safety Guardrails

Policy, filtering, and technical controls that block disallowed or risky outputs.

How it connects

Guardrails operationalize Alignment in real deployments.

In practice

Needed to prevent harmful content or data leaks when models generate freely.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 9

28Expert
PDF essentials

Temperature

A sampling parameter controlling randomness during text generation: lower values make outputs more predictable; higher values more creative.

How it connects

Guardrails constrain what’s allowed; Temperature shapes style within safe bounds.

In practice

A simple dial teams adjust for creativity vs. reliability.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 9

29Expert
PDF essentials

Hallucination

When a model confidently generates information that is false or not found in its training data.

How it connects

Higher Temperature and weak Guardrails can increase Hallucinations.

In practice

Mitigating hallucinations is vital for trustworthy business applications.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 10

30Expert
PDF essentials

Evaluation Metrics

Quantitative or qualitative measures (e.g., accuracy, BLEU, human ratings) used to judge a model’s performance and safety.

How it connects

Metrics quantify how well we control Hallucinations and meet Alignment goals.

In practice

Continuous evaluation guides improvement cycles for production-grade generative systems.

Ken Tabor · Generative AI: 30 Must-Know Terms · Source page 10

31Beginner
Foundations

Supervised learning

Training on examples paired with known target labels or values.

How it connects

Unlike unsupervised learning, it has labeled targets.

In practice

Train an image classifier using labeled photos.

Reference: Google ML Glossary

32Beginner
Foundations

Unsupervised learning

Finding structure or patterns in data without target labels.

How it connects

Clustering is one unsupervised approach.

In practice

Group similar customer messages without predefined classes.

Reference: Google ML Glossary

33Intermediate
Foundations

Reinforcement learning

Learning a policy through interactions and reward signals.

How it connects

Unlike supervised learning, feedback evaluates actions and outcomes.

In practice

Train a controller to choose actions that increase reward.

Reference: Google ML Glossary

34Beginner
Foundations

Classification

Predicting a discrete category for an input.

How it connects

A supervised task distinct from numeric regression.

In practice

Classify messages as spam or not spam.

Reference: Google ML Glossary

35Beginner
Foundations

Regression

Predicting a numerical value from input features.

How it connects

A supervised task distinct from classification.

In practice

Estimate a delivery time in minutes.

Reference: Google ML Glossary

36Beginner
Foundations

Training set

The examples used to fit a model's learned parameters.

How it connects

Kept separate from test examples for honest evaluation.

In practice

Train a classifier on the training split.

Reference: Google ML Glossary

37Intermediate
Foundations

Validation set

Held-out examples used during development to choose settings or models.

How it connects

Unlike the test set, it informs model selection.

In practice

Select a checkpoint using validation performance.

Reference: Google ML Glossary

38Beginner
Foundations

Test set

Held-out examples reserved to assess a model after development.

How it connects

Repeated tuning on test results can contaminate the estimate.

In practice

Report final accuracy on untouched test examples.

Reference: Google ML Glossary

39Intermediate
Foundations

Overfitting

Learning training-specific patterns that do not generalize well.

How it connects

Often appears as a widening training–validation gap.

In practice

Use validation data to spot memorization.

Reference: Google ML Glossary

40Intermediate
Foundations

Underfitting

Failing to capture useful patterns even in training data.

How it connects

Contrasts with overfitting rather than merely low test accuracy.

In practice

Increase model capacity when both training and validation fit poorly.

Reference: Google ML Glossary

41Intermediate
Foundations

Gradient descent

An optimization method that updates parameters in a loss-reducing direction.

How it connects

Uses gradients typically computed by backpropagation.

In practice

Update neural-network weights during training.

Reference: Google ML Glossary

42Expert
Foundations

Backpropagation

Computing gradients through a neural network using the chain rule.

How it connects

Provides gradients to an optimizer such as gradient descent.

In practice

Calculate how each weight contributes to training loss.

Reference: Google ML Glossary

43Intermediate
Model architecture

Encoder

A model component that converts input into internal representations.

How it connects

An encoder can feed a decoder or a task-specific head.

In practice

Encode a document for classification or retrieval.

Reference: Hugging Face Transformers Glossary

44Intermediate
Model architecture

Decoder

A model component that produces an output sequence from representations.

How it connects

Decoder-only language models predict text autoregressively.

In practice

Generate a response token by token.

Reference: Hugging Face Transformers Glossary

45Expert
Model architecture

Encoder–decoder model

Architecture that encodes an input sequence and decodes a target sequence.

How it connects

Cross-attention can connect decoder steps to encoder outputs.

In practice

Translate a sentence from one language to another.

Reference: Hugging Face Transformers Glossary

46Intermediate
Model architecture

Self-attention

Attention in which positions attend to representations from the same sequence.

How it connects

A central component of Transformer blocks.

In practice

Relate words at different positions in a document.

Reference: Google ML Glossary

47Expert
Model architecture

Cross-attention

Attention where queries attend to representations from another sequence or source.

How it connects

Links decoder states to encoded input or other modalities.

In practice

Generate a caption conditioned on image features.

Reference: Google ML Glossary

48Expert
Model architecture

Attention head

One parallel attention computation within a multi-head attention layer.

How it connects

Multiple heads can learn different relationships.

In practice

Inspect attention patterns across a Transformer layer.

Reference: Hugging Face Transformers Glossary

49Expert
Model architecture

Positional encoding

Position information supplied to a sequence model so token order is represented.

How it connects

Complements content embeddings in attention architectures.

In practice

Distinguish swapped word orders in a sentence.

Reference: Google ML Glossary

50Intermediate
Model architecture

Attention mask

An indicator of which token positions a model may attend to.

How it connects

Can hide padding or enforce causal visibility.

In practice

Prevent padded positions affecting a batched input.

Reference: Hugging Face Transformers Glossary

51Expert
Model architecture

Causal attention

Attention that prevents a position from seeing future positions.

How it connects

Supports left-to-right autoregressive generation.

In practice

Train a next-token predictor without future-token leakage.

Reference: Google ML Glossary

52Expert
Model architecture

Softmax

A function converting numeric scores into a normalized probability distribution.

How it connects

Often turns attention scores or output logits into weights.

In practice

Convert candidate-token scores into probabilities.

Reference: Google ML Glossary

53Intermediate
Model architecture

Activation function

A function introducing nonlinearity into a neural-network layer.

How it connects

Without nonlinearities, stacked linear layers remain linear.

In practice

Apply a nonlinear transformation inside a model block.

Reference: Google ML Glossary

54Intermediate
Model architecture

Autoregressive generation

Producing each new token conditioned on previously generated tokens.

How it connects

Uses a decoding strategy to choose successive tokens.

In practice

Continue a paragraph one token at a time.

Reference: Google ML Glossary

55Beginner
Prompting

Prompt engineering

Designing and revising instructions and examples to guide model output.

How it connects

Narrower than context engineering, which manages all supplied information.

In practice

Specify a format and provide representative examples.

Reference: Anthropic: Context Engineering

56Beginner
Prompting

System instruction

A higher-priority instruction configuring a model's role or behavior.

How it connects

Distinct from a user's request or retrieved source text.

In practice

Set assistant responsibilities before taking user input.

Reference: Google ML Glossary

57Beginner
Prompting

Zero-shot prompting

Requesting a task without including worked examples in the prompt.

How it connects

Contrasts with few-shot prompting.

In practice

Ask a model to classify a sentence from instructions alone.

Reference: Google ML Glossary

58Beginner
Prompting

Few-shot prompting

Including a small set of examples in a prompt to demonstrate a task.

How it connects

Uses in-context learning without changing model weights.

In practice

Show input–output examples before a new classification.

Reference: Google ML Glossary

59Intermediate
Prompting

Prompt chaining

Connecting separate model calls so earlier outputs feed later steps.

How it connects

A predetermined workflow rather than an open-ended agent loop.

In practice

Generate an outline, critique it, then draft the article.

Reference: Anthropic: Building Effective Agents

60Beginner
Prompting

Prompt template

A reusable instruction structure with placeholders for variable inputs.

How it connects

Keeps consistent framing while changing task-specific content.

In practice

Insert a customer question into a reviewed template.

Reference: Google ML Glossary

61Intermediate
Prompting

Structured output

Model output constrained or validated against a defined data shape.

How it connects

Often used with typed schemas and tool interfaces.

In practice

Return machine-readable fields for downstream code.

Reference: OpenAI Agents SDK

62Expert
Prompting

Top-k sampling

Selecting the next token from only the k highest-scoring candidates.

How it connects

A decoding restriction distinct from nucleus sampling.

In practice

Limit candidate tokens before sampling a response.

Reference: Hugging Face Generation Strategies

63Expert
Prompting

Nucleus sampling (top-p)

Sampling from the smallest set of tokens whose cumulative probability reaches p.

How it connects

Unlike top-k, candidate-set size changes with the distribution.

In practice

Control the diversity of generated text.

Reference: Hugging Face Generation Strategies

64Intermediate
Retrieval

Retrieval-augmented generation (RAG)

Generating with relevant information retrieved from an external source.

How it connects

Retrieval supplements model parameters with task-time context.

In practice

Answer a policy question from indexed documents.

Reference: Anthropic: Context Engineering

65Intermediate
Retrieval

Document chunking

Splitting source material into retrievable pieces.

How it connects

Chunk boundaries affect what a retriever can return.

In practice

Divide a handbook into passages before indexing.

Reference: Anthropic: Context Engineering

66Intermediate
Retrieval

Chunk overlap

Repeating some content across adjacent document chunks.

How it connects

Can preserve context across chunk boundaries at a storage cost.

In practice

Keep a sentence spanning two passages discoverable.

Reference: Anthropic: Context Engineering

67Intermediate
Retrieval

Vector database

A system that stores vectors and supports similarity-oriented retrieval.

How it connects

A vector index accelerates searches within such storage.

In practice

Find semantically related product descriptions.

Reference: Weaviate: Vector Indexing

68Expert
Retrieval

Vector index

A search structure organizing vectors for similarity queries.

How it connects

May use HNSW or a flat index depending on scale.

In practice

Speed up nearest-neighbor retrieval.

Reference: Weaviate: Vector Indexing

69Intermediate
Retrieval

Semantic search

Retrieving items by vector-based meaning similarity rather than exact words.

How it connects

Complements keyword search in hybrid retrieval.

In practice

Match 'car repair' with documents about vehicle servicing.

Reference: Weaviate: Hybrid Search

70Beginner
Retrieval

Keyword search

Matching indexed text against the words in a query.

How it connects

Useful for exact names that semantic similarity might miss.

In practice

Find a specific product code in documentation.

Reference: Weaviate: Keyword Search

71Expert
Retrieval

BM25

A lexical ranking function using term frequency and collection statistics.

How it connects

Often forms the keyword branch of hybrid search.

In practice

Rank documents containing exact query terms.

Reference: Weaviate: Keyword Search

72Intermediate
Retrieval

Hybrid search

Combining vector similarity results with lexical keyword results.

How it connects

Balances meaning-based retrieval with exact-term matching.

In practice

Search a knowledge base containing both concepts and part numbers.

Reference: Weaviate: Hybrid Search

73Intermediate
Retrieval

Reranking

Reordering an initial set of retrieval results using an additional relevance signal.

How it connects

Applied after first-stage candidate retrieval.

In practice

Promote the most relevant passages before answering.

Reference: Google ML Glossary

74Expert
Retrieval

Approximate nearest neighbor (ANN)

Finding nearby vectors efficiently without guaranteeing exact exhaustive results.

How it connects

HNSW is one approximate-neighbor indexing method.

In practice

Scale semantic search across millions of vectors.

Reference: Weaviate: Vector Indexing

75Expert
Retrieval

HNSW

A hierarchical graph index for approximate nearest-neighbor search.

How it connects

Trades index complexity for fast vector queries.

In practice

Index a large embedding collection for low-latency search.

Reference: Weaviate: Vector Indexing

76Expert
Retrieval

Cosine similarity

A measure comparing vector direction using the cosine of their angle.

How it connects

One way to score embedding similarity.

In practice

Compare query and passage representations.

Reference: Google ML Glossary

77Intermediate
Model adaptation

Supervised fine-tuning (SFT)

Training a pretrained model further on labeled instruction–response examples.

How it connects

A distinct adaptation stage from preference optimization.

In practice

Teach a model an organization's response format.

Reference: Google ML Glossary

78Intermediate
Model adaptation

Instruction tuning

Fine-tuning on examples of instructions paired with desired responses.

How it connects

A form of supervised adaptation for following tasks.

In practice

Improve responses to varied user instructions.

Reference: Google ML Glossary

79Expert
Model adaptation

Direct preference optimization (DPO)

Optimizing a language model from pairs of preferred and dispreferred responses.

How it connects

An alternative preference-learning approach to RLHF pipelines.

In practice

Train from human pairwise response choices.

Reference: Google ML Glossary

80Intermediate
Model adaptation

Parameter-efficient fine-tuning (PEFT)

Adapting a model by training a small subset of extra or selected parameters.

How it connects

Includes methods such as LoRA and prompt tuning.

In practice

Customize an LLM with lower training-memory demand.

Reference: Hugging Face PEFT Methods

81Expert
Model adaptation

Low-rank adaptation (LoRA)

Training low-rank weight updates while keeping original model weights frozen.

How it connects

A widely used parameter-efficient fine-tuning method.

In practice

Ship a compact domain-specific adapter.

Reference: Hugging Face LoRA Guide

82Expert
Model adaptation

QLoRA

Training LoRA adapters against a quantized base model.

How it connects

Combines parameter-efficient adaptation with reduced base-model memory.

In practice

Fine-tune a large model on limited GPU memory.

Reference: Hugging Face PEFT Methods

83Intermediate
Model adaptation

Adapter module

A small trainable component attached to a largely frozen model.

How it connects

LoRA is one adapter-based approach.

In practice

Swap specialized behavior without full model copies.

Reference: Hugging Face PEFT Methods

84Expert
Model adaptation

Prompt tuning

Learning continuous prompt parameters while keeping the pretrained model frozen.

How it connects

Unlike ordinary prompting, the prompt parameters are trained.

In practice

Learn task-specific virtual-token embeddings.

Reference: Hugging Face PEFT Methods

85Expert
Model adaptation

Prefix tuning

Learning a small continuous prefix to steer a frozen model.

How it connects

Related to prompt tuning but modifies prefix representations.

In practice

Adapt a model to a specialized generation task.

Reference: Hugging Face PEFT Methods

86Intermediate
Model adaptation

Transfer learning

Reusing learned representations or parameters for another task.

How it connects

Fine-tuning is a common transfer-learning technique.

In practice

Adapt an image model to a smaller labeled dataset.

Reference: Google ML Glossary

87Expert
Model adaptation

Knowledge distillation

Training a smaller student model to imitate a teacher model.

How it connects

Can transfer behavior into a cheaper model.

In practice

Build a lower-latency assistant from teacher outputs.

Reference: Google ML Glossary

88Intermediate
Model adaptation

Quantization

Representing model weights or activations with lower numerical precision.

How it connects

Trades numerical precision for memory or compute savings.

In practice

Serve a model using 8-bit weights.

Reference: vLLM Overview

89Expert
Inference systems

KV cache

Stored attention keys and values reused across autoregressive decoding steps.

How it connects

Avoids recomputing prior-token attention projections.

In practice

Accelerate long conversational generations.

Reference: vLLM: Automatic Prefix Caching

90Expert
Inference systems

Prefix caching

Reusing cached attention state for requests sharing an identical prefix.

How it connects

Builds on KV cache reuse across requests.

In practice

Reuse a common system prompt without recomputation.

Reference: vLLM: Automatic Prefix Caching

91Expert
Inference systems

Continuous batching

Dynamically adding and removing inference requests from active batches.

How it connects

Improves GPU utilization compared with rigid request batches.

In practice

Serve varying-length chat requests together.

Reference: vLLM Overview

92Expert
Inference systems

PagedAttention

An attention-memory approach that manages KV cache in blocks.

How it connects

Helps reduce KV-memory fragmentation during serving.

In practice

Increase concurrent model requests on a GPU.

Reference: vLLM Overview

93Expert
Inference systems

Prefill

The inference phase that processes an input prompt before generating new tokens.

How it connects

Precedes the iterative decode phase.

In practice

Measure the cost of ingesting a long prompt.

Reference: vLLM Overview

94Expert
Inference systems

Decode phase

The iterative stage that emits new tokens after prompt processing.

How it connects

Can reuse the attention KV cache built during prefill.

In practice

Optimize per-token serving latency.

Reference: vLLM Overview

95Intermediate
Inference systems

Time to first token (TTFT)

Elapsed time from a request to its first generated token.

How it connects

Includes waiting and initial prompt processing.

In practice

Track responsiveness of a streaming assistant.

Reference: vLLM Overview

96Intermediate
Inference systems

Throughput

Amount of work completed per unit of time, such as output tokens per second.

How it connects

Different from single-request latency.

In practice

Measure aggregate serving capacity under load.

Reference: vLLM Overview

97Expert
Inference systems

Speculative decoding

Using draft predictions that a target model verifies to speed decoding.

How it connects

Targets generation speed while preserving target-model checks.

In practice

Accelerate token production with a small draft model.

Reference: vLLM Overview

98Intermediate
Inference systems

Context window

The model's bounded token capacity for input and, depending on the model, output.

How it connects

Context engineering chooses what occupies this capacity.

In practice

Budget documents and message history before a call.

Reference: Anthropic: Context Engineering

99Beginner
Inference systems

Streaming generation

Delivering partial model output as it is produced.

How it connects

Changes perceived responsiveness without guaranteeing faster total completion.

In practice

Show answer tokens progressively in a chat UI.

Reference: vLLM Overview

100Beginner
Agents and workflows

AI agent

A system that uses a model and tools to pursue a task through multiple steps.

How it connects

An agent differs from a fixed-path workflow in who chooses steps.

In practice

Research an issue, call tools, then synthesize findings.

Reference: Anthropic: Building Effective Agents

101Intermediate
Agents and workflows

Agent loop

Repeating model decisions and tool executions until a stop condition.

How it connects

Core runtime cycle underneath many tool-using agents.

In practice

Continue searching until evidence is sufficient.

Reference: LangChain: Context Engineering

102Intermediate
Agents and workflows

Tool calling

A model selecting a named tool and providing its arguments.

How it connects

A runtime executes the tool and returns observations to the model.

In practice

Request a database lookup through a schema.

Reference: OpenAI Agents SDK

103Beginner
Agents and workflows

Tool result

The observation returned to an agent after a tool executes.

How it connects

Becomes new context for the next model decision.

In practice

Use a search result to decide the next query.

Reference: LangChain: Context Engineering

104Intermediate
Agents and workflows

Agent orchestration

Coordinating agent steps, tools, state, and handoffs.

How it connects

Can be implemented by a harness or graph runtime.

In practice

Control a multi-step research-and-write task.

Reference: LangGraph: Workflows and Agents

105Intermediate
Agents and workflows

Agent handoff

Transferring control from one agent to another specialist.

How it connects

Unlike using an agent as a tool, the recipient takes over control.

In practice

Route a billing question to a billing agent.

Reference: OpenAI Agents SDK

106Intermediate
Agents and workflows

Subagent

A delegated agent working on a bounded subtask, often with separate context.

How it connects

A harness can run subagents in parallel.

In practice

Delegate test-writing while a parent handles implementation.

Reference: LangChain: Agent Harness

107Intermediate
Agents and workflows

Multi-agent system

A solution composed of multiple interacting agents.

How it connects

Coordination determines how work and state are shared.

In practice

Use specialized research and verification agents.

Reference: Anthropic: Building Effective Agents

108Intermediate
Agents and workflows

Routing workflow

Classifying an input and sending it down an appropriate predefined path.

How it connects

An explicit workflow pattern, not necessarily an autonomous agent.

In practice

Route support tickets to different handlers.

Reference: Anthropic: Building Effective Agents

109Intermediate
Agents and workflows

Parallelization workflow

Running independent tasks simultaneously and combining their outputs.

How it connects

Trades extra concurrent work for reduced wall-clock time.

In practice

Research multiple independent sources in parallel.

Reference: LangGraph: Workflows and Agents

110Expert
Agents and workflows

Orchestrator–worker workflow

A coordinator decomposes work and assigns dynamically chosen subtasks to workers.

How it connects

Handles tasks whose substeps cannot all be fixed in advance.

In practice

Divide a report into specialist research assignments.

Reference: LangGraph: Workflows and Agents

111Expert
Agents and workflows

Evaluator–optimizer loop

Alternating generation and feedback until a quality condition is met.

How it connects

A distinct pattern from a fixed single-pass chain.

In practice

Revise a translation after evaluating terminology accuracy.

Reference: LangGraph: Workflows and Agents

112Intermediate
Agents and workflows

Stop condition

A criterion that ends an agent's iterative execution.

How it connects

Can be model completion, iteration budget, or goal satisfaction.

In practice

Stop a tool loop once all required fields are verified.

Reference: Claude: Getting Started with Loops

113Intermediate
Agent engineering

Context engineering

Selecting and maintaining useful instructions, tools, history, and retrieved data for a model call.

How it connects

Broader than optimizing the wording of a single prompt.

In practice

Trim stale tool outputs and retrieve only needed files.

Reference: Anthropic: Context Engineering

114Expert
Agent engineering

Harness engineering

Designing code, constraints, tools, tests, and feedback around a model so it can work reliably.

How it connects

The harness provides an execution environment beyond model weights.

In practice

Make a coding agent run checks and inspect repository state.

Reference: OpenAI: Harness Engineering

115Expert
Agent engineering

Loop engineering

Designing how agent work cycles are triggered, repeated, observed, and stopped; an emerging term.

How it connects

More about execution cycles than prompt wording alone.

In practice

Run a bounded coding loop until tests pass or a limit is reached.

Reference: Claude: Getting Started with Loops

116Expert
Agent engineering

Agent harness

The surrounding runtime and configuration that gives a model tools, state, and constraints.

How it connects

Harness engineering is the practice of building that runtime.

In practice

Give an agent a sandbox, planning tool, and test feedback.

Reference: LangChain: Agent Harness

117Intermediate
Agent engineering

Agent state

Stored information describing an agent's current execution and intermediate results.

How it connects

Checkpoints save state so execution can resume.

In practice

Keep plan status and accumulated research across steps.

Reference: LangGraph: Persistence

118Intermediate
Agent engineering

Checkpoint

A saved snapshot of workflow state at an execution boundary.

How it connects

Enables replay, recovery, and human approval.

In practice

Resume after a failed tool rather than restarting the run.

Reference: LangGraph: Persistence

119Expert
Agent engineering

Durable execution

Persisting enough progress to resume a workflow after interruption.

How it connects

Uses checkpoints and careful handling of side effects.

In practice

Continue a multi-hour job after a worker restarts.

Reference: LangGraph: Persistence

120Intermediate
Agent engineering

Human approval gate

A pause that requires a person's decision before an action proceeds.

How it connects

Can be implemented with graph interrupts and persistent state.

In practice

Require approval before sending an email.

Reference: LangGraph: Persistence

121Intermediate
Agent engineering

Short-term agent memory

Run- or thread-scoped information retained across nearby agent turns.

How it connects

Usually backed by conversation state or checkpoints.

In practice

Recall the current task's previous tool results.

Reference: LangGraph: Persistence

122Expert
Agent engineering

Long-term agent memory

Information stored beyond a single run for later retrieval.

How it connects

Distinct from the immediate context window.

In practice

Retrieve a past preference from a persistent store.

Reference: Anthropic: Context Engineering

123Expert
Agent engineering

Context compaction

Condensing earlier messages or observations to free context capacity.

How it connects

Trades detail for a smaller active working context.

In practice

Summarize completed tool calls before continuing.

Reference: Anthropic: Context Engineering

124Expert
Agent engineering

Just-in-time retrieval

Loading information when an agent needs it instead of placing everything in context upfront.

How it connects

A context-engineering strategy that limits irrelevant tokens.

In practice

Open a referenced file only when its contents are required.

Reference: Anthropic: Context Engineering

125Expert
Agent engineering

Sandboxed execution

Running agent actions in an isolated, constrained environment.

How it connects

A harness boundary that reduces unintended system access.

In practice

Execute generated code in a disposable workspace.

Reference: LangChain: Agent Harness

126Intermediate
Agent protocols

Model Context Protocol (MCP)

A protocol for connecting AI applications to external tools, resources, and prompts.

How it connects

Separates host, client, and server roles.

In practice

Expose a documentation tool to an assistant.

Reference: Model Context Protocol: Architecture

127Intermediate
Agent protocols

MCP host

The application coordinating MCP client connections and permission decisions.

How it connects

A host may create a separate client for each server.

In practice

Manage tool access within a desktop AI application.

Reference: Model Context Protocol: Architecture

128Intermediate
Agent protocols

MCP client

A component maintaining one connection from a host to an MCP server.

How it connects

Negotiates capabilities with its server.

In practice

Connect an assistant to a repository service.

Reference: Model Context Protocol: Architecture

129Intermediate
Agent protocols

MCP server

A service exposing specialized tools, resources, or prompts over MCP.

How it connects

May run locally or remotely from the host.

In practice

Offer file-search functionality to multiple clients.

Reference: Model Context Protocol: Architecture

130Intermediate
Agent protocols

MCP tool

A callable capability advertised by an MCP server.

How it connects

Tool execution is distinct from reading an MCP resource.

In practice

Invoke a repository search with typed arguments.

Reference: Model Context Protocol: Architecture

131Intermediate
Agent protocols

MCP resource

A server-exposed piece of contextual data that a client can read.

How it connects

Resources provide context rather than executable actions.

In practice

Read a project document through a resource URI.

Reference: Model Context Protocol: Architecture

132Intermediate
Agent protocols

MCP prompt

A server-provided reusable prompt template or message pattern.

How it connects

Different from a callable MCP tool.

In practice

Load a standard code-review prompt from a server.

Reference: Model Context Protocol: Architecture

133Expert
Agent protocols

Capability negotiation

The initialization exchange declaring supported protocol features.

How it connects

Clients and servers must respect negotiated capabilities.

In practice

Enable sampling only if both sides support it.

Reference: Model Context Protocol: Architecture

134Expert
Agent protocols

JSON-RPC

A structured request/response messaging protocol used by MCP.

How it connects

Forms the base for messages between MCP components.

In practice

Send a typed tool-call request to a server.

Reference: Model Context Protocol: Architecture

135Intermediate
Evaluation

Offline evaluation

Testing application behavior on a curated dataset before deployment.

How it connects

Can compare changes against reference answers.

In practice

Check a new prompt on a held-out question set.

Reference: LangSmith Evaluation

136Intermediate
Evaluation

Online evaluation

Scoring real production interactions as they occur.

How it connects

Complements offline testing with live traffic coverage.

In practice

Flag format failures on sampled production traces.

Reference: LangSmith Evaluation

137Intermediate
Evaluation

Golden dataset

A curated test collection with trusted reference cases or expected outputs.

How it connects

Serves as a repeatable baseline for regression evaluation.

In practice

Keep reviewed questions and target answers for a RAG bot.

Reference: LangSmith Evaluation

138Expert
Evaluation

LLM-as-a-judge

Using a language model as an evaluator under defined grading criteria.

How it connects

May require reference answers and calibration with human labels.

In practice

Judge whether a summary follows provided evidence.

Reference: LangSmith Evaluation

139Intermediate
Evaluation

Pairwise evaluation

Comparing two candidate outputs directly rather than assigning standalone scores.

How it connects

Useful when relative quality is easier to judge.

In practice

Compare two assistant responses for clarity.

Reference: LangSmith Evaluation

140Intermediate
Evaluation

Precision

Among predicted positives, the fraction that are truly positive.

How it connects

Complements recall and depends on the decision threshold.

In practice

Measure how often flagged spam is actually spam.

Reference: Google ML Glossary

141Intermediate
Evaluation

Recall

Among actual positives, the fraction the model correctly identifies.

How it connects

Can trade off against precision.

In practice

Measure how much harmful content a filter catches.

Reference: Google ML Glossary

142Expert
Evaluation

F1 score

The harmonic mean of precision and recall.

How it connects

Balances two classification measures in one statistic.

In practice

Compare extraction systems when both errors matter.

Reference: Google ML Glossary

143Intermediate
Evaluation

Regression test

A repeatable check that detects behavior worsening after a change.

How it connects

Can be run on a fixed evaluation dataset.

In practice

Verify a prompt edit does not break previous cases.

Reference: LangSmith Evaluation

144Intermediate
AI safety

Prompt injection

Instructions in input that try to redirect a model away from its intended task or rules.

How it connects

Can arrive through direct messages or external content.

In practice

Treat retrieved web text as untrusted data.

Reference: OWASP: Prompt Injection

145Expert
AI safety

Indirect prompt injection

Malicious instructions embedded in content an assistant retrieves or encounters.

How it connects

Crosses a trust boundary when source text is treated as commands.

In practice

Ignore tool-result text requesting secret disclosure.

Reference: OWASP: Prompt Injection

146Expert
AI safety

Excessive agency

Giving an agent more permissions or autonomy than its task requires.

How it connects

Increases the impact of failures or prompt injection.

In practice

Limit a research agent to read-only tools.

Reference: OWASP: Excessive Agency

147Intermediate
AI safety

Least privilege

Granting only the permissions necessary for an operation.

How it connects

Constrains the blast radius of agent mistakes.

In practice

Give a summarizer no delete-file capability.

Reference: OWASP: Excessive Agency

148Intermediate
AI safety

Input guardrail

A check applied to incoming content before or alongside agent processing.

How it connects

Distinct from checks on final outputs and tool calls.

In practice

Reject an out-of-scope request before expensive processing.

Reference: OpenAI Agents SDK

149Intermediate
AI safety

Output guardrail

A check validating the final answer before it is returned.

How it connects

Complements input validation and tool-level checks.

In practice

Block a response containing restricted information.

Reference: OpenAI Agents SDK

150Intermediate
AI safety

Execution trace

A record of an operation's model calls, tool events, and handoffs.

How it connects

Contains spans that help locate failures.

In practice

Inspect which tool call produced a bad answer.

Reference: OpenAI Agents SDK: Tracing

151Intermediate
Generative media

Multimodal model

A model that processes or produces more than one data modality.

How it connects

Can combine text with images, sound, or video.

In practice

Answer a question about an attached chart.

Reference: Google ML Glossary

152Beginner
Generative media

Computer vision

Methods that process and interpret images or video.

How it connects

Often provides image representations to multimodal systems.

In practice

Identify objects in a photograph.

Reference: Google ML Glossary

153Intermediate
Generative media

Automatic speech recognition (ASR)

Converting spoken audio into text.

How it connects

Can provide transcribed text to a language model.

In practice

Transcribe a voice message for summarization.

Reference: Google ML Glossary

154Intermediate
Generative media

Text-to-speech (TTS)

Generating spoken audio from written text.

How it connects

Can turn an assistant's textual answer into speech.

In practice

Read a generated explanation aloud.

Reference: Google ML Glossary

155Expert
Generative media

Diffusion model

A generative model that learns to reverse a noise-adding process.

How it connects

A scheduler guides denoising during sample generation.

In practice

Generate an image from random noise and a prompt.

Reference: Hugging Face: Diffusion Pipeline

156Expert
Generative media

Denoising step

One update that moves a noisy sample toward a cleaner sample.

How it connects

Repeated steps form a diffusion sampling trajectory.

In practice

Generate an image across a sequence of timesteps.

Reference: Hugging Face: Diffusion Schedulers

157Expert
Generative media

Diffusion scheduler

An algorithm specifying timesteps and updates for diffusion denoising.

How it connects

Works with the denoising network during inference.

In practice

Choose a scheduler that trades steps for quality.

Reference: Hugging Face: Diffusion Schedulers

158Expert
Generative media

Classifier-free guidance

Combining conditioned and unconditioned noise predictions to steer generation.

How it connects

Guidance scale controls how strongly a prompt influences output.

In practice

Adjust adherence to a text-to-image prompt.

Reference: Hugging Face: Diffusion Pipeline

159Intermediate
AI safety

Guardrails

Checks and validations placed around model or agent execution to detect, block, or handle inputs, outputs, or tool actions that violate defined rules.

How it connects

An umbrella concept that includes input, output, and tool guardrails; it complements least-privilege permissions and prompt-injection defenses.

In practice

Block an unsafe request before an agent runs, or reject a final answer that fails a policy check.

Reference: OpenAI Agents SDK: Guardrails

160Intermediate
Agents and workflows

Model routing

Selecting which model or specialized processing path should handle a request based on task type, difficulty, cost, latency, or capability needs.

How it connects

Routing can send easy requests to smaller models and harder requests to stronger models; it is related to, but narrower than, routing an entire workflow.

In practice

Classify routine support questions to a fast model while sending ambiguous cases to a more capable reasoning model.

Reference: Anthropic: Building Effective Agents

161Intermediate
Inference systems

Prompt caching

Reusing previously computed model state for a shared prompt prefix so repeated input does not need to be processed from scratch.

How it connects

It builds on reusable KV state for identical prefixes and differs from semantic caching, which can reuse whole responses for meaning-equivalent queries.

In practice

Keep stable system instructions and tool definitions at the beginning of requests so later calls can reuse the cached prefix.

Reference: OpenAI API: Prompt caching

162Expert
Agent engineering

Effective context

The high-signal subset of available information that is actually useful for the model's current decision, rather than every token that could fit inside the context window.

How it connects

A context window is the model's capacity limit; effective context is an engineering goal of filling that capacity with the smallest useful set of instructions, history, tools, and retrieved data.

In practice

Drop stale tool outputs and retrieve only the files needed for the next agent step instead of filling the full context window.

Reference: Anthropic: Context Engineering

163Expert
Inference systems

Semantic caching

Reusing a previously generated response when a new request is semantically similar enough to a cached request, rather than requiring an exact prompt match.

How it connects

Unlike prompt caching, a semantic-cache hit can skip the LLM call entirely; similarity thresholds and metadata boundaries are important to avoid returning the wrong cached answer.

In practice

Serve the same validated answer for paraphrased requests when similarity, tenant, and freshness checks pass.

Reference: Redis: Semantic cache

164Intermediate
Agent engineering

Token budget

An application-level allocation for how many tokens a task or model call should spend across instructions, retrieved context, conversation history, tool results, reasoning, and output.

How it connects

It turns finite context and attention capacity into an explicit engineering constraint, often alongside compaction, truncation, and just-in-time retrieval.

In practice

Reserve space for the final answer and cap retrieved passages so a long tool result cannot crowd critical instructions out of the model's working context.

Reference: Anthropic: Context Engineering

165Intermediate
Evaluation

Evaluation set (eval set)

A curated collection of representative test cases used to measure an AI system repeatedly under defined evaluators or metrics.

How it connects

It is the dataset used for offline evals; some eval sets include trusted reference answers, while others contain inputs plus rubric-based or programmatic grading criteria.

In practice

Keep a reviewed set of support questions and expected behaviors, then rerun it after prompt, model, retrieval, or tool changes to catch regressions.

Reference: LangSmith Evaluation

The first 30 cards retain the original descriptions and author-assigned levels from Generative AI: 30 Must-Know Terms by Ken Tabor (June 1, 2025), pages 4–10. Additional cards are original summaries of linked primary sources; their difficulty levels are editorial learning guidance, not source classifications. Emerging terminology may vary by organization. Source links and structural checks support review but are not a guarantee of factual correctness.