What AI Is in 2026: From ChatGPT to Agents in Your Terminal
Published: 2026-06-01 · Last updated: 2026-06-01 · 13 min read
There is so much marketing around artificial intelligence that it is hard to separate what actually works from the promises on a slide. This piece sorts that out. No jargon where it is not needed, and concrete numbers where they matter: how it works, what it costs, what you are allowed to do, and where the limits are. We wrote it for the people who make decisions and for the people who then have to implement them.
Every number here (prices, model versions) reflects the state of things in June 2026. This market changes by the week, so treat them as a snapshot, not a constant. The last-updated date sits at the top of the post.
First, honestly: what AI is not
When we say "AI" in a business context, 95% of the time we mean large language models (LLMs): ChatGPT, Claude, Gemini, and their peers. They run on one principle: they take text and predict the most likely next fragment, piece by piece, until an answer forms (IBM, Google for Developers).
This leads to four misconceptions that cost companies real money:
- "AI understands what it writes." Not in a human sense. The model picks probable words from patterns in its training data. Fluency and a confident tone are not proof of truth.
- "We just need to switch off the errors." Hallucinations, answers that sound credible but are false, are built into how these models work. A 2025 OpenAI paper shows that the way models are trained and graded actually rewards confident guessing over saying "I don't know" (OpenAI: Why Language Models Hallucinate). You can reduce them, you cannot turn them off.
- "It's just a better search engine." The model alone does not browse the internet. It generates from what it learned up to a cutoff date. To work with current or company data, you have to supply it through a separate mechanism (RAG).
- "It learns from my conversation in real time." During a conversation the model learns nothing. Its knowledge is frozen after training. It only remembers what fits in the current session.
The takeaway for a decision-maker is simple: AI is a powerful tool for language and patterns, not an oracle. Where the cost of a mistake is high (law, finance, medicine), a human stays in the decision loop.
How it works, in three paragraphs
The model splits text into tokens (words or fragments of words), then runs them through a network of billions of parameters: numbers tuned during training to predict the next token accurately. The architecture that made this possible is the transformer, and its heart is the attention mechanism (self-attention), which lets the model weigh which words in a sentence matter to each other (Google for Developers).
There are two separate phases. Training is a one-off, expensive process of learning from huge text collections. Inference is the everyday use of the finished model. During inference the parameters are frozen, so the model does not remember conversations (unless you deliberately build it a memory).
One operational concept matters: the context window, how much text the model "sees" at once, its working memory. In 2026 the standard is 128 thousand tokens (roughly a thick book), and the best models reach a million. A practical caveat: even within the limit, quality drops for information buried in the middle of a long context (the "lost in the middle" effect, DataAnnotation). A bigger window is not a magic fix.
Where does classic machine learning fit? AI is the broadest term, machine learning sits inside it, deep networks inside that, and generative models inside those. A classic ML model predicts and classifies ("is this transaction fraud?"). A generative model creates new content ("write a reply to this customer"). Different tools for different jobs (Salesforce, MIT Sloan).
The same model, four different ways to use it
This is the distinction missing from most conversations about AI. GPT-5.5 or Claude Opus is the same model no matter how you use it. What changes is the access channel, and with it cost, control, privacy, and how much autonomy the system gets.
| Chat | API | Terminal tools (CLI) | Agent | |
|---|---|---|---|---|
| Who it's for | every employee | product teams | developers, DevOps | supervised tasks |
| Billing | flat fee (~$20/mo) | per usage (token) | token or subscription | token (grows fast) |
| Control | low | high | high (files and commands) | variable |
| Trains on your data | consumer: yes (opt-out); business: no | no | depends on channel | depends on channel |
| Main risk | data leaking into training | integration errors | system access | reliability |
Chat (ChatGPT, Claude.ai, the Gemini app) is the interface everyone knows. Great for ad hoc work: writing, research, summaries. There is a trap here, covered below.
The API is programmatic access: you embed the model into your own product or process and pay for the tokens you actually use. Full control over behaviour, parameters, and logging, but also full responsibility for the quality of the integration.
Terminal tools (Claude Code, OpenAI Codex CLI, Gemini CLI, the open-source aider) are the bridge between chat and a full agent. The model does more than answer: it reads and edits files in your project, runs commands, and tests the result itself. This is a daily tool for developers (CLI comparison, CodeAnt).
Agents are systems that work in a loop: the model reasons, picks a tool, takes an action, checks the result, and decides the next step. We return to them in their own section, because this is where marketing diverges most from reality.
Privacy: same company, different terms
The most common mistake in companies is pasting data into free or personal chat. The reason is concrete: consumer plans train on your content by default.
Anthropic changed its terms on 28 September 2025: Claude Free, Pro, and Max accounts (including work in Claude Code from those accounts) are used to train the model unless the user turns the option off. For accounts that allow training, data retention grew from 30 days to five years (Anthropic, TechCrunch). Google uses conversations from consumer Gemini by default until you turn off your activity (Google). The same applies to ChatGPT on Free/Plus plans.
Business plans are a different regime. ChatGPT Team and Enterprise, Claude for Work, and API access from all three vendors do not train on customer data by default (OpenAI Enterprise privacy, Anthropic). Same model underneath, entirely different contract.
The model landscape: as of June 2026
Flagship model numbering changes so fast that any table ages within weeks. Below is a June 2026 snapshot, prices in USD per million tokens (input and output separately). One thing the price list hides: "thinking" (reasoning) tokens are billed like output, so the real cost of reasoning-heavy tasks can be many times the headline rate.
| Vendor | Example model | Input / Output (USD/1M) | Context |
|---|---|---|---|
| OpenAI | GPT-5.5 | 5.00 / 30.00 | ~1M |
| Anthropic | Claude Opus 4.8 | 5.00 / 25.00 | 1M |
| Anthropic | Claude Sonnet 4.6 | 3.00 / 15.00 | 1M |
| Gemini 3.1 Pro | 2.00 / 12.00 | 2M | |
| Mistral (EU) | Mistral Large 3 | 0.50 / 1.50* | 256K |
Prices: OpenAI, Anthropic, Google, Mistral. *For Mistral Large 3 two different rates circulate (the official one and third-party hosting providers); confirm at the source before a purchase decision.
Alongside the commercial models, a world of open-weight models keeps growing, ones you can download and run yourself: Llama (Meta), Mistral, Qwen, DeepSeek, and in the Polish context Bielik (the SpeakLeash Foundation and Cyfronet AGH) plus the state-backed PLLuM. Bielik 11B is the best model under 20 billion parameters on the Polish leaderboard and ships under the open Apache 2.0 licence (technical report, arXiv). Honestly: Polish models do not beat GPT or Gemini on raw quality. Their value is the Polish language, an open licence, EU-law compliance, and independence from US vendors.
Local or cloud: and, while we're at it, sovereignty
For most companies, cloud and the API are cheaper and simpler. Self-hosting a model only starts to pay off at large, steady volume (on the order of several million tokens a day against premium-class models) and only if the GPUs are actually busy (TCO analysis, SitePoint). Hardware cost is just the tip: power, maintenance, and engineer time pile on top. The huge advertised context windows are often theoretical on your own GPU, because the memory needed to serve them grows steeply.
There is a second axis, purely legal. "Servers in Europe" is not the same as data sovereignty. The US CLOUD Act lets US authorities demand access to data held by a US company even if the servers sit in Frankfurt (Lyceum Technology). For a company handling personal or sensitive data, that is a strong argument for hosting with a provider subject only to EU law, or for running an open model (Bielik, for example) on your own infrastructure.
AI agents: where the demo ends and production begins
Agents are the loudest topic of 2026 and also the easiest place to be fooled. The idea is real: a system works on its own in a loop until it finishes a task. The products exist: ChatGPT Agent (OpenAI), Claude Agent SDK (Anthropic), Devin (an autonomous engineer), Manus.
The problem is reliability. A Princeton study documents the gap: model capabilities grow faster than their reliability, and reliability drops exactly where a task has many steps, which is the condition that defines the promise of agents (arXiv, Fortune). Devin in 2025 reported that 67% of its pull requests get merged, but only for tasks with clear requirements and a verifiable result (Cognition).
The takeaway for a company is balanced. Agents work in narrow, repeatable tasks with a measurable outcome. For ambiguous or risky work, the standard remains a human in the loop: autonomy within boundaries that a person sets and controls.
What this means for a Polish company
The hard numbers speak for themselves. In 2025, 8.7% of Polish companies used AI according to the national statistics office (GUS) and 8.4% according to Eurostat, which puts Poland second from the bottom in the EU against a 20% average (GUS via PAP, Eurostat). For the leaders (Denmark, 42%) that is a competitive advantage. For most Polish companies it is still open ground.
Proven uses today are process automation, customer service, document workflows (sped up by the mandatory e-invoicing system, KSeF), debt collection, and coding assistance. Filter the marketing as you go: claims like "the bot handles 80% of queries" are vendor statements, not audited results.
Above all this sits the EU AI Act. Banned practices and the AI-literacy obligation apply from February 2025, obligations for large models from August 2025, and most of the remaining provisions from August 2026 (European Commission). A simplification package (the Digital Omnibus) is in the works and would push back some high-risk deadlines, but as of June 2026 it is only a political agreement, not binding law. When you plan a deployment, assume the base deadlines.
Frequently asked questions
Are ChatGPT, Claude, and Gemini the same thing? They are competing models from different companies (OpenAI, Anthropic, Google). They differ in capability, price, and character, but run on the same language-model principle. The choice depends on the task, the budget, and your legal requirements.
Is my data safe with AI? It depends on the plan, not the vendor. Free and personal chat usually trains on your content. Business plans and API access do not by default. Check the terms of the specific plan before you enter company data.
Do I need an expensive model? Rarely for everything. Cheaper, faster models handle most routine tasks. Save the most expensive ones for work that needs complex reasoning. Matching the model to the task is the biggest lever for savings.
Will AI replace employees? In 2026 AI takes over tasks, not roles: repetitive, high-volume, pattern-based work. Judgement, accountability, and decisions about consequences stay with people. The best deployments combine the two.
Where to start
If you are reading this as a decision-maker, the first step is not choosing a model. It is choosing one process where AI will cut time or cost, and an honest assessment of what data that process touches. Everything else, including the choice between chat, the API, and a local model, follows from those two answers.
At ITEON we do exactly that: we start with the process and the data, and we pick the technology last. If you want to move from "interesting" to "it works", let's talk about an AI deployment.
Sources
Every claim in this text rests on a primary source. Pricing and model-version data reflect the state of things in June 2026 and need periodic updates.
How models work
- Large Language Models, IBM
- Introduction to LLMs, Google for Developers and Transformers
- Generative AI vs Machine Learning, Salesforce, MIT Sloan
- Context window and "lost in the middle", DataAnnotation
- Why Language Models Hallucinate, OpenAI (arXiv 2509.04664)
Pricing and model comparisons
- OpenAI pricing, Anthropic, Google Gemini, Mistral
- Artificial Analysis: model comparison
- Bielik 11B technical report (arXiv)
Data privacy
- Consumer terms update, Anthropic, TechCrunch
- Is my data used for training, Anthropic, Enterprise privacy, OpenAI, Gemini Apps, Google
Tools, agents, costs
- CLI tools comparison, CodeAnt
- Towards a Science of AI Agent Reliability, Princeton (arXiv), Fortune
- Devin Performance Review 2025, Cognition
- Local LLMs vs cloud, TCO analysis, data sovereignty and the CLOUD Act, Lyceum
Market data and regulation