ai /Practical AI0 / 55 lessons complete

A SHARED VOCABULARY

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Agent frameworks

Agent frameworks provide reusable building blocks for model calls, tools, task state, orchestration, and related agent behaviors. Their scope and abstractions vary.

Level 06 · Navigate the ecosystem

Agent loops

An agent loop repeats a cycle of choosing a step, taking an allowed action, observing the result, and deciding what to do next.

Level 04 · Let AI do work

AI agents

An AI agent is a system that uses a model to choose and perform steps toward a goal, often using tools and feedback. The term covers systems with very different levels of autonomy.

Level 04 · Let AI do work

AI gateways

An AI gateway is an intermediary through which applications access model services. Depending on the implementation, it can centralize routing, usage tracking, limits, and credentials.

Level 06 · Navigate the ecosystem

APIs

An application programming interface, or API, is a defined way for software systems to request information or operations from each other.

Level 06 · Navigate the ecosystem

Approval gates

An approval gate pauses a proposed operation until an authorized person approves the specific action under the required conditions.

Level 05 · Make it reliable

Chunking

Chunking splits larger source material into smaller units for indexing and retrieval. A useful chunk keeps a coherent piece of meaning together.

Level 02 · Give AI knowledge

Confidence thresholds

A confidence threshold determines when a system accepts a result and when it asks for clarification, review, or a different method. Its usefulness depends on the signal behind the score.

Level 03 · Shape the behavior

Context windows

The context window is the model’s capacity for information within one request. Instructions, conversation history, retrieved documents, tool results, and output all compete for a finite budget, subject to the model’s limits.

Level 01 · Understand AI

Cost and latency

Cost is the resource or monetary expense of a task. Latency is the time a user waits for a useful result. Both depend on the whole workflow, not only one model call.

Level 05 · Make it reliable

Deterministic vs probabilistic systems

A deterministic rule produces the same result from the same inputs under the same conditions. A probabilistic model works with likelihoods, and generation may also involve sampling from those likelihoods.

Level 01 · Understand AI

Embedding models vs LLMs

An embedding model produces representations useful for comparison. A generative large language model produces sequences, usually text. Both learn patterns, but their outputs and jobs differ.

Level 01 · Understand AI

Embeddings

An embedding is a list of numbers representing features of an input, such as text. For semantic search, the model is trained so useful similarities are reflected in the relationships between these lists.

Level 01 · Understand AI

Evals

Evals are systematic tests of how well an AI system performs its intended task. They turn a vague impression of quality into evidence you can compare.

Level 05 · Make it reliable

Fallbacks

A fallback is a planned alternative when the preferred AI path cannot complete a task reliably or safely.

Level 03 · Shape the behavior

Few-shot prompting

Few-shot prompting supplies a small set of examples showing the desired input-to-output pattern within the request.

Level 03 · Shape the behavior

Fine-tuning

Fine-tuning is additional training that adjusts a model using a selected dataset to improve a target behavior or task.

Level 03 · Shape the behavior

GPUs and inference

GPUs are processors designed for large amounts of parallel computation. They are widely used for the numerical operations involved in training and running AI models.

Level 06 · Navigate the ecosystem

Grounding

Grounding means anchoring an answer in relevant evidence supplied to the system, such as a policy, a database result, or an observed tool response.

Level 02 · Give AI knowledge

Guardrails

Guardrails are checks and controls that limit unacceptable inputs, outputs, or actions around an AI system.

Level 05 · Make it reliable

Hallucinations

A hallucination is an output that is fabricated, unsupported, or inconsistent with the relevant evidence. It can sound just as confident as a correct answer.

Level 01 · Understand AI

Handling cross-references

A cross-reference points from one part of a source to another, such as ‘subject to section 8.’ Retrieval must preserve or follow that relationship when the referenced material affects the answer.

Level 02 · Give AI knowledge

Hugging Face

Hugging Face provides a platform and tools for working with machine-learning models and datasets. Its Hub hosts repositories where model artifacts and documentation can be shared.

Level 06 · Navigate the ecosystem

Human-in-the-loop

Human-in-the-loop means a person participates at a defined point in an AI-assisted process to review, correct, approve, or resolve uncertainty.

Level 04 · Let AI do work

Inference vs training

Training changes a model’s learned parameters using data. Inference runs an existing model on new input to produce an output.

Level 01 · Understand AI

Local models

A local model runs on hardware you operate, such as a laptop, workstation, or private server, rather than sending inference requests to an external model service.

Level 06 · Navigate the ecosystem

Memory

Application memory is information retained for use beyond the current interaction, such as preferences, summaries, or selected prior events.

Level 04 · Let AI do work

Metadata

Metadata is descriptive information attached to content: its source, owner, date, region, document type, section, or access classification.

Level 02 · Give AI knowledge

Model Context Protocol (MCP)

MCP is a protocol for connecting AI applications with external capabilities and context through a common interface.

Level 06 · Navigate the ecosystem

Model families and sizes

A model family is a related group of models. Variants may differ in size, training, supported inputs, reasoning behavior, and operational requirements.

Level 01 · Understand AI

Model routing

Model routing selects a model or processing path for a task instead of sending every request to the same model.

Level 03 · Shape the behavior

Model serving

Model serving is the operational layer that accepts requests, runs a model, and returns results to applications.

Level 06 · Navigate the ecosystem

NVIDIA Cosmos

NVIDIA Cosmos is a platform and family of world-model capabilities aimed at physical AI: systems that interpret, generate, or reason about physical environments.

Level 06 · Navigate the ecosystem

Observability

Observability is the ability to understand a system’s behavior from signals such as logs, metrics, traces, and user feedback.

Level 05 · Make it reliable

Ollama

Ollama is software for using supported models through local applications and APIs. Its ecosystem includes both locally run and cloud model options.

Level 06 · Navigate the ecosystem

Open vs closed models

Models vary in how much is available to inspect, modify, and run. Open weights means the learned parameters are available; it does not necessarily mean training data, training code, or unrestricted usage rights are available.

Level 01 · Understand AI

Orchestration

Orchestration coordinates the models, tools, people, and services that make up a larger process.

Level 04 · Let AI do work

Parent-child retrieval

Parent-child retrieval searches smaller passages but returns a larger containing section when more context is needed.

Level 02 · Give AI knowledge

Permissions

Permissions define which identities may access particular data or perform particular operations. They should be enforced by the application and the systems it calls.

Level 05 · Make it reliable

Prompt injection

Prompt injection happens when untrusted content tries to redirect a model’s behavior by presenting itself as an instruction.

Level 05 · Make it reliable

Prompt templates

A prompt template is a reusable structure that combines stable instructions with task-specific inputs.

Level 03 · Shape the behavior

Reliability vs autonomy

Autonomy is how much a system can decide and do without intervention. Reliability is how consistently it achieves acceptable outcomes. They are separate properties.

Level 05 · Make it reliable

Reranking

Reranking is a second pass that reorders retrieved candidates using a more focused assessment of their relevance to the question.

Level 02 · Give AI knowledge

Retrieval-augmented generation (RAG)

RAG combines finding relevant information with generating an answer from it. The system retrieves evidence at the time of the question instead of relying only on the model’s training.

Level 02 · Give AI knowledge

Semantic chunking

Semantic chunking chooses boundaries using changes in meaning or topic, rather than only a fixed character or token count.

Level 02 · Give AI knowledge

Similarity search

Similarity search ranks items by how close their representations are to a query. In semantic search, that closeness is intended to capture useful relationships in meaning.

Level 02 · Give AI knowledge

State

State is the explicit record of where a task currently stands: inputs collected, steps completed, approvals received, actions taken, and work still pending.

Level 04 · Let AI do work

Structured output

Structured output returns information in a defined format, such as a record with fixed fields and allowed categories, rather than only free-form prose.

Level 03 · Shape the behavior

System prompts

A system prompt is an instruction supplied by the application to define the model’s role, priorities, and expected behavior. Products differ in how they name and prioritize instruction layers.

Level 03 · Shape the behavior

Temperature

Temperature is a generation setting that changes how strongly a model favors likely next tokens. Lower settings generally concentrate the choices; higher settings allow more variation.

Level 01 · Understand AI

Tokens

Tokens are the small units a language model processes. A token can be a word, part of a word, a number fragment, or punctuation. The split depends on the model’s tokenizer and the language.

Level 01 · Understand AI

Tool calling

Tool calling lets a model request a defined operation from another system, such as looking up an order or preparing a calendar event.

Level 04 · Let AI do work

Tracing

A trace connects the steps of a single task so you can follow its path through retrieval, model calls, tools, validations, and approvals.

Level 05 · Make it reliable

Vector databases

A vector database stores numerical representations and supports searching for nearby vectors. Many also store text and metadata or combine vector search with other search methods.

Level 02 · Give AI knowledge

Workflows vs agents

A workflow follows a predefined process. An agent uses a model to decide more of the process dynamically. Many practical systems combine these patterns.

Level 04 · Let AI do work