# Claude Claude is a [[Large Language Models (LLMs)]] created by [[Anthropic]]. There are multiple variants of Claude: - Haiku - Sonnet - Opus - Mythos class (Fable / Mythos) Those evolve over time. As of September 2026, the most powerful model is [[Claude Fable 5.1]] (the Mythos-class flagship, above the Opus line; point release of [[Claude Fable 5]]), with [[Claude Opus 5.5]] as the strongest of the Opus line (Fable 5.1-level results on most work) and [[Claude Sonnet 5.5]] as the latest mid-tier model (close to Opus 5.5 on many benchmarks at half the token price; it also powers the free tier on claude.ai). Sonnet 5.5's direct competitor at the same price ($2/$10) is GPT-6 Sol; Opus 5.5 is usually compared with [[GPT-6 Astra]]. Note that Fable 5 and Mythos 5 were pulled worldwide on 2026-06-12 by a US export-control directive. See [[2026-06-17 The US Government Banned Claude Fable 5 and Mythos 5|Fable 5 ban]]. I personally consider Claude as superior to [[GPT4]] (all variants) and [[Gemini]]. There's a free and a different paid tiers. ## One Claude: chat and Cowork merged (September 2026) On 2026-09-16, Anthropic announced that [[Claude Cowork]] and chat are merging into a single Claude, rolling out to Pro and Max over a few weeks. [[Claude Design]] is folded in too, so you can ask for a slide deck, a design or a doc without switching tabs or apps. The idea, according to [[Cat Wu]]: people didn't want to choose which Claude product to use for a task, and the models are now good enough to route for you. Based on the prompt, Claude decides whether to answer quickly or do deeper agentic work, and which kind of output fits. You can still stop it, redirect it, or control effort and approach. Hand over a report, close the laptop, and Claude keeps working. When something's unclear, it asks. I like this. The Chat / Cowork / Code tab split always leaked the org chart into the UI. Routing is exactly the kind of decision a capable model should make for me. ## Projects Claude Projects enable creating a stable "context" for conversations with Claude. Within the context of a project, Claude will already know what you have discussed before. It's useful when working on a project, to avoid having to repeat the same information over and over (e.g., project goals, scope, current status, previously discussed ideas, etc). On a Claude Project page, it's possible to configure the "Project" knowledge, that is, the starting context for all discussions. The Project knowledge can be defined using: - Custom instructions (i.e., a prompt) - Content (e.g., documents, text, images, etc) Not to be confused with [[Claude Code Projects]] (September 2026), where one conversation orchestrates parallel cloud threads. ## Styles Claude supports selecting different output styles. Some are built in, but it's also possible to create custom styles. Here's an introduction to this feature:  ## Computer Use See [[Claude Computer use]]. ## Desktop ### Introduction Anthropic provides an official desktop client for Claude. Since November 2024, Claude Desktop has become MUCH more powerful, because it can be integrated with arbitrary data sources through Anthropic's new open standard called [[Model Context Protocol (MCP)]]. ### Feature previews Click on your name in the bottom left corner, then select "Feature Preview" to view and enable feature previews. ### Integrate with Google Drive Claude can access data stored in Google Drive. To connect your account, click on your name in the bottom left corner, then choose "Settings", then click on "Connect" in the "Connected accounts" section. After connecting your account, a Google Drive icon will appear below the chat box, allowing you to load recent Google Drive files, or files by URL. ### Configuration - On Windows, the configuration is located in `%appdata%/Claude` - On MacOS, it is under `~/Library/Application Support/Claude` For configuring MCP, please look at [[Model Context Protocol (MCP)]]. ## Code Claude also has a CLI called [[Claude Code]]. ## Design [[Claude Design]] is Anthropic's Labs product for generating designs, prototypes, slides, and one-pagers through conversation, with handoff to [[Claude Code]] for implementation. ## Managed Agents [[Claude Managed Agents]] is Anthropic's cloud-hosted agent harness — run Claude as an autonomous agent in a secure container without building the loop yourself. See also [[Anthropic CLI (ant)]]. ## Developer Platform Building software on top of Claude happens through the [[Claude Platform]]: the [[Claude API]], the [[Claude Console]] web dashboard, docs, a cookbook, and official SDKs. The cookbook (https://platform.claude.com/cookbook/) is the fastest way to learn current best practices: working recipes for tool use, agent patterns, RAG, prompt caching, batch processing, extended thinking, and more. See [[Claude Platform]] for the highlights. ## Model Context Protocol (MCP) Support Claude Desktop has deep support for [[Model Context Protocol (MCP)]] servers. It acts as an MCP client, but also supports [[Desktop Extensions for MCP]], enabling easy installation of local MCP servers: ![[Claude - DesktopExts Support.png]] ## References - Official Website: https://claude.ai/ - Claude Downloads: https://claude.ai/download - Anthropic's Website: https://www.anthropic.com/ - Claude Projects: https://www.anthropic.com/news/projects - Claude Styles: https://www.anthropic.com/news/styles - Cowork and chat merge (Cat Wu, 2026-09-16): https://x.com/_catwu/status/2100260655312089562 A comparison of Custom [[ChatGPT]] GPTs and Claude Projects: