Meta Muse acts as a cloud agent, while ChatGPT, Claude, and Grok each act in different places.
API base rates run from USD 1.25 to USD 10 per million input tokens, with higher rates for long prompts on Astra and Grok.
All four companies announced major model or product releases within weeks of each other in September 2026.
Four AI companies released major products within weeks of each other this September. Meta launched an agent called Muse, whereas OpenAI shipped GPT-6 Astra. Anthropic rolled out Fable 5.1, Opus 5.5, and Sonnet 5.5. SpaceXAI released Grok 4.7. Each system now tries to finish tasks, not only answer questions. That makes the Meta Muse AI vs ChatGPT vs Claude vs Grok choice a practical one.
Chatbots once waited for a prompt and returned text. Now, Agents work differently. They plan steps, open browsers, write code, and use connected apps. A fair comparison looks at where each system acts, what it can reach, and how much control the user keeps.
Meta launched Muse on September 8 as a personal AI agent. It runs on a virtual machine in Meta's cloud. A built-in browser lets the user watch the work. At launch, Muse is free, with paid plans at USD 20 and USD 100 a month. Meta says it carries no ads. Availability starts in the United States on iOS, Android, and the web.
The Mac app reaches local files, calendars, notes, and messages with user permission. CNN reported that Muse topped Apple's free app chart ten days after launch. Muse runs on Muse Spark 1.3, which arrived on September 2. That model takes text, image, and video input.
OpenAI released GPT-6 Astra on September 3. Astra is available on Plus, Pro, Business, and Enterprise plans. Astra Pro is available on Pro, Business, and Enterprise plans. OpenAI says about one billion people use ChatGPT every week. The app also offers three entry points. Chat handles conversation, Codex handles coding, and Work handles office tasks.
Anthropic released Fable 5.1 on September 1. Mythos 5.1 is the same model with different safeguards. Only vetted participants in trusted-access programs can use it, mostly for cybersecurity and life sciences. Opus 5.5 arrived on September 22 for complex work that needs careful judgment.
Sonnet 5.5 followed on September 28 as a faster, lower-cost complement. It suits bug fixes, documents, slides, and spreadsheets. Haiku 5.5 is due in the coming weeks. Claude Code, Cowork, and Claude in Chrome handle agent work. Anthropic says its Claude products carry no ads.
SpaceXAI released Grok 4.7 on September 21. It searches the web and X. It also runs code. It accepts text and image input. It offers four reasoning levels. Grok Build handles coding in the terminal. The company was called xAI until July, and Grok kept its name. Grok 5 is still in training.
| Assistant | Underlying Model | Context | API Price, Base Rate (Input / Output) | Agent Approach |
|---|---|---|---|---|
| Meta Muse | Muse Spark 1.3 | 1M tokens | USD 1.25 / USD 4.25 | Personal cloud agent |
| ChatGPT | GPT-6 Astra | 1.05M tokens | USD 10 / USD 50 (under 272K) | Chat, Codex, Work |
| Claude | Opus 5.5 | Varies by model | USD 4 / USD 20 | Code, Cowork, Chrome |
| Grok | Grok 4.7 | 500K tokens | USD 2 / USD 6 (under 200K) | X, web, and coding |
Astra's input rate is eight times that of Muse Spark 1.3, and long prompts raise the bill further. Astra charges twice the input rate and 1.5 times the output rate for requests over 272,000 tokens. Grok also raises its rates for long prompts.
Safety methods differ in design. OpenAI says Astra crossed its critical cybersecurity threshold and limited its strongest cyber capabilities. Anthropic separates Fable and Mythos by safeguard level. Muse acts only with the permissions the user grants.
The use cases are also distinct. Muse suits personal tasks. ChatGPT spans a broad set of work tools. Claude emphasizes professional reasoning and coding. Grok emphasizes real-time information.
Openness is narrow. All four flagship models are closed-weight. Meta separately offers Muse Glimmer, an open 30-billion-parameter model. A Muse Spark open-weight release is promised but undated.
Also Read: ChatGPT, Perplexity, Gemini, Claude, or Grok: Which Has the Best Subscription Plans?
An agent can act for a user only when it can reach personal data. That means files, accounts, and messages. Each company handles this in its own way. Meta leans on its large audience. It also asks users for permission.
OpenAI offers many tools to choose from. Anthropic sets careful limits on what its models can do. SpaceXAI draws on live posts from X. These products change fast. A comparison can go stale in weeks. Readers should pick a tool based on the job at hand. They should also check the latest model details first.
Also Read: Claude AI vs ChatGPT: Which AI Assistant is Better in 2026?
Trust will likely shape the next round. Agents that ask for approval at every step feel slow. Agents that never ask often feel risky. The company that finds the balance first will set the standard for the rest.
Meta Muse AI is a personal AI agent designed to handle tasks for users. It uses Meta’s Muse Spark model and can work across different tasks beyond basic question answering.
Meta Muse focuses on personal agent-based tasks, while ChatGPT offers a broader set of tools through GPT-6 Astra, including Chat, Codex, and Work.
Muse Spark 1.3 is the AI model that powers Meta Muse. It supports text, image, and video inputs and is designed for agent-based tasks.
Claude uses Anthropic’s Claude 5.5 model family, including Opus 5.5 and Sonnet 5.5. Grok uses Grok 4.7 from SpaceXAI.
The choice depends on the task. Users should compare agent capabilities, available tools, context limits, pricing, data access and safety controls before selecting a platform.