--- title: Brain, Tools, Memory, Loop: AI Agents 101 | daily.dev description: A beginner-friendly breakdown of the four core components that make up every AI agent: the Brain (an LLM that makes decisions), Tools (actions the agent can... canonical: https://daily.dev/posts/brain-tools-memory-loop-ai-agents-101-6pgduurfw twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Brain, Tools, Memory, Loop: AI Agents 101 | daily.dev og:description: A beginner-friendly breakdown of the four core components that make up every AI agent: the Brain (an LLM that makes decisions), Tools (actions the agent can... og:url: https://daily.dev/posts/brain-tools-memory-loop-ai-agents-101-6pgduurfw og:image: https://api.daily.dev/og/posts/6pGduURfw.png og:image:alt: Brain, Tools, Memory, Loop: AI Agents 101 og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Brain, Tools, Memory, Loop: AI Agents 101 **[Medium](https://daily.dev/sources/medium_js)** · 4 min read · 0 upvotes · 0 comments ## Summary A beginner-friendly breakdown of the four core components that make up every AI agent: the Brain (an LLM that makes decisions), Tools (actions the agent can take), Memory (tracking past steps and results), and the Loop (the cycle that ties everything together). A simple example using math and weather queries illustrates how all four parts work in concert. The post teases a follow-up where readers will build a minimal agent in Python. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [2. Anatomy of an Agent](https://daily.dev/posts/2-anatomy-of-an-agent-iudwpzseq) · Planet Python · 3 upvotes · 0 comments - [What you need to make an agent](https://daily.dev/posts/what-you-need-to-make-an-agent-0zdqdjckf) · swizec.com · 1 upvotes · 0 comments - [Everything You Need to Know Before Building AI Agents](https://daily.dev/posts/everything-you-need-to-know-before-building-ai-agents-ube2oh8qr) · BigData Boutique blog · 13 upvotes · 0 comments --- Tags: [#python](https://daily.dev/tags/python), [#llm](https://daily.dev/tags/llm), [#ai-agents](https://daily.dev/tags/ai-agents) [View this post on daily.dev](https://daily.dev/posts/brain-tools-memory-loop-ai-agents-101-6pgduurfw) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Brain, Tools, Memory, Loop: AI Agents 101","url":"https://daily.dev/posts/brain-tools-memory-loop-ai-agents-101-6pgduurfw","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/brain-tools-memory-loop-ai-agents-101-6pgduurfw"},"datePublished":"2026-07-12T12:10:34.018Z","dateModified":"2026-07-12T12:12:03.461Z","description":"A beginner-friendly breakdown of the four core components that make up every AI agent: the Brain (an LLM that makes decisions), Tools (actions the agent can...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/da7f079edcdc8633ed68316db3b57daa?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/da7f079edcdc8633ed68316db3b57daa?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Medium","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Medium","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/medium","url":"https://daily.dev/sources/medium_js"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/brain-tools-memory-loop-ai-agents-101-6pgduurfw","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"python,llm,ai-agents","timeRequired":"PT4M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Medium","item":"https://daily.dev/sources/medium_js"},{"@type":"ListItem","position":3,"name":"Brain, Tools, Memory, Loop: AI Agents 101"}]} ```