---
title: "Knowledge: fundamentals"
summary: "Knowledge Base entries tagged “fundamentals”."
published: 2026-11-09
updated: 2026-11-09
language: en
tags: ["fundamentals"]
canonical: https://joaodavidsilva.com/knowledge/tags/fundamentals/
---

# Knowledge tagged “fundamentals”

- [Agent](https://joaodavidsilva.com/knowledge/agent.md): A model harnessed with tools, a system prompt and a context window that takes turns with a user: the unit you actually talk to.
- [Context](https://joaodavidsilva.com/knowledge/context.md): The task-relevant information the agent has access to right now, as distinct from the context window and the session.
- [Context window](https://joaodavidsilva.com/knowledge/context-window.md): Everything the model sees on each model provider request: finite, model-specific, and the only surface through which it perceives anything.
- [Model](https://joaodavidsilva.com/knowledge/model.md): The parameters: a stateless next-token predictor that can't do anything agentic until it is harnessed.
- [Token](https://joaodavidsilva.com/knowledge/token.md): The atomic unit a model reads and writes; context window size, cost and latency are all counted in tokens.