Glossary

What is AI Agents?

Concept By David Hamilton
Definition

AI Agents is aI systems that take a goal, plan a sequence of steps, and use tools to carry them out, rather than just answering a single question.

What makes something an “agent”

An AI agent is a model that does more than answer. It takes a goal, figures out a plan, picks tools to carry the plan out, observes what happens, and iterates until the job is done. The model is still at the core. What is new is the loop around it.

A chatbot is one-shot: question in, answer out. An agent is a loop: think, act, observe, repeat. That loop is what lets an agent debug code, browse documentation, read files, check the results, and try again when something breaks.

By 2026, “agent” has become shorthand for any AI system that combines reasoning with tool use. Claude Code is an agent. Cursor’s agentic mode is an agent. Autonomous research tools like browser-use and computer-use systems are agents. The line between “AI assistant” and “agent” is getting thinner every month.

The core capabilities

Most useful agents need four things.

Tool use. The agent can call functions to take actions: run a search, read a file, execute code, hit an API. Without tools, the agent is still just a chatbot with fancy prompting.

Planning. The agent can break a goal into steps. Sometimes this is explicit (plan-then-execute) and sometimes it emerges from the reasoning itself.

Memory. The agent can track state across steps, remember what it has tried, and incorporate new information. For short tasks, the context window handles this. For longer tasks, external memory systems come into play.

Observability. The agent can see what happened after each action. Tool output comes back. Errors get noticed. The loop keeps going until the task resolves.

Strip any of these out and you are back to a regular chat model.

Why MCP matters for agents

Before MCP, every agent-to-tool connection was custom code. Want your agent to use your database? Write a wrapper. Want it to read your bookmarks? Build an integration. Want it to call your internal API? Write more wrapper code. Each tool was bespoke, which is why agent ecosystems stayed small.

The Model Context Protocol fixes this. An MCP server exposes tools in a standard format. Any compatible agent can discover and use them without custom integration. This is the same unlock that HTTP gave the web: one protocol, infinite endpoints.

The practical effect is that agents now have an ecosystem. You can connect Claude Code to a file system server, a database server, a Jira server, and ContextBolt for your bookmarks, all at once, without writing any glue. The agent just sees more tools.

What agents are actually doing in 2026

The most common real-world agent workloads right now:

The common thread is tasks where the agent can check its own work. Code either runs or it does not. A query either returns data or errors. Feedback loops are what make agents reliable.

Agents and your saved content

One underused pattern: giving an agent access to the things you have read. Most agents are trained on the open web but know nothing about what you personally have saved or learned. Adding your bookmarks as a tool changes this.

If you have saved 2,000 articles on a topic over years, an agent with access to those saves has context no base model has. It can ground its answers in your specific knowledge, cite sources you trust, and stay consistent with positions you have already endorsed. That is what tools like ContextBolt make possible through MCP. Your reading becomes context for the agent, not just for you.

Related terms

Frequently asked questions

What is the difference between a chatbot and an AI agent? +
A chatbot answers questions from its own knowledge. An agent can take actions: call tools, read files, hit APIs, loop over its own output, and keep working until the task is done. Claude Code is an agent. A basic Q&A bot is not.
Do AI agents use MCP? +
Increasingly yes. The Model Context Protocol is rapidly becoming the standard way to give agents access to tools and data. Claude Desktop, Claude Code, Cursor, and Windsurf all use MCP. It means an agent can connect to new capabilities without custom code, just by adding an MCP server.
Are AI agents reliable? +
It depends on the task and the model. Well-scoped tasks with clear tools and good context work reliably. Open-ended multi-step tasks across unfamiliar systems are still error-prone. The gap is closing fast, but agents are not a replacement for reviewing important output yet.
How can I give an agent access to my bookmarks? +
Through an MCP server. ContextBolt exposes your Twitter/X, Reddit, and LinkedIn saves as a search tool. Any agent that supports MCP can connect and query your saved content as part of its reasoning. Setup takes a few minutes.
What tasks are AI agents actually good at today? +
Writing and editing code, research synthesis across multiple sources, data analysis with tool calls, drafting and refining documents, and coordinating small multi-step workflows. They struggle with tasks that require real-world judgment, persistent memory across long sessions, or high-stakes decisions.