Grok 4.1 Fast

Grok 4.1 Fast

SpaceXSI
+
+

Related Products

  • Gemini Enterprise Agent Platform
    1,161 Ratings
    Visit Website
  • FinOpsly
    3 Ratings
    Visit Website
  • Checksum.ai
    2 Ratings
    Visit Website
  • LM-Kit.NET
    29 Ratings
    Visit Website
  • LTX
    182 Ratings
    Visit Website
  • Concord
    237 Ratings
    Visit Website
  • Jotform
    9,009 Ratings
    Visit Website
  • StackAI
    55 Ratings
    Visit Website
  • Evertune
    1 Rating
    Visit Website
  • Google AI Studio
    42 Ratings
    Visit Website

About

Claude Fable 5.5 is not currently an announced or released Anthropic model. Anthropic's current model documentation lists Claude Fable 5.1 as the latest Fable model alongside Claude Opus 5.5 and Claude Sonnet 5.5. Fable 5.1 remains Anthropic's premium model for demanding reasoning and long-horizon agentic workloads, with a 1-million-token context window and maximum output of 128,000 tokens. It uses adaptive thinking that is always enabled and defaults to a high reasoning effort level. Fable 5.1 is priced at $10 per million input tokens and $50 per million output tokens, with cache reads priced at $0.25 per million tokens. Anthropic has released Opus 5.5 and Sonnet 5.5, but there is currently no official model documentation, pricing, release date, benchmark data, or API identifier for Claude Fable 5.5.

About

Grok 4.1 Fast is an xAI model designed to deliver advanced tool-calling capabilities with a massive 2-million-token context window. It excels at complex real-world tasks such as customer support, finance, troubleshooting, and dynamic agent workflows. The model pairs seamlessly with the new Agent Tools API, which enables real-time web search, X search, file retrieval, and secure code execution. This combination gives developers the power to build fully autonomous, production-grade agents that plan, reason, and use tools effectively. Grok 4.1 Fast is trained with long-horizon reinforcement learning, ensuring stable multi-turn accuracy even across extremely long prompts. With its speed, cost-efficiency, and high benchmark scores, it sets a new standard for scalable enterprise-grade AI agents.

Platforms Supported

Windows Not Supported
Mac Not Supported
Linux Not Supported
Cloud Supported
On-Premises Not Supported
iPhone Not Supported
iPad Not Supported
Android Not Supported
Chromebook Not Supported

Platforms Supported

Windows Not Supported
Mac Not Supported
Linux Not Supported
Cloud Supported
On-Premises Not Supported
iPhone Supported
iPad Supported
Android Supported
Chromebook Not Supported

Audience

Developers, AI researchers, enterprises, software engineering teams, and advanced professional users handling demanding reasoning and long-horizon agentic workloads, although Anthropic has not yet announced the model or specified its intended audience

Audience

This content is ideal for developers, enterprises, and technical teams seeking to build advanced AI agents that require real-time data access, long-context reasoning, and reliable tool-calling capabilities

Support

Phone Support Not Supported
24/7 Live Support Not Supported
Online Supported

Support

Phone Support Not Supported
24/7 Live Support Not Supported
Online Supported

API

Offers API Supported

API

Offers API Supported

Screenshots and Videos

No images available

Screenshots and Videos

Pricing

No information available.
Free Version Not Supported
Free Trial Not Supported

Pricing

No information available.
Free Version Not Supported
Free Trial Not Supported

Reviews/Ratings

Overall 0.0 / 5
ease 0.0 / 5
features 0.0 / 5
design 0.0 / 5
support 0.0 / 5

This software hasn't been reviewed yet. Be the first to provide a review:

Review this Software

Reviews/Ratings

Overall 5.0 / 5
ease 5.0 / 5
features 5.0 / 5
design 5.0 / 5
support 5.0 / 5

Pros & Cons from Real Users

Pros

  • Grok 4.1 Fast is one of the most capable agentic AI models available today, combining frontier-level intelligence with blazing speed and exceptional tool-calling performance. Its 2M-token context window enables consistent reasoning over extremely long conversations, multi-turn workflows, and complex planning. Thanks to extensive RL training across diverse simulated environments, the model excels in real-world scenarios such as customer support, finance, research, and autonomous decision-making. Paired with the new Agent Tools API—featuring real-time X search, internet browsing, code execution, file retrieval, and MCP integration—Grok 4.1 Fast can orchestrate multi-step tasks seamlessly and autonomously. Benchmark results reinforce its strengths, outperforming or rivaling leading models across tool calling, long-context reasoning, and multihop search.

Cons

  • Because Grok 4.1 Fast is designed for sophisticated agentic use cases, developers new to tool-calling workflows may face a learning curve when integrating its advanced capabilities. Its reasoning variant is optimized for accuracy rather than instant response time, which may feel slower compared to lightweight chat models. And while pricing is competitive—especially with free access via OpenRouter—the cost of high-volume tool calls may add up for large enterprise workloads once promotional periods end.

Training

Documentation Supported
Webinars Not Supported
Live Online Not Supported
In Person Not Supported

Training

Documentation Supported
Webinars Not Supported
Live Online Not Supported
In Person Not Supported

Company Information

Anthropic
Founded: 2021
United States
claude.ai

Company Information

SpaceXSI
Founded: 2023
United States
grok.com

Alternatives

Alternatives

GPT-6.1 Sol

GPT-6.1 Sol

OpenAI
Grok 4.8

Grok 4.8

SpaceXSI
Claude Fable 5

Claude Fable 5

Anthropic
Grok 4.5

Grok 4.5

SpaceXSI

Categories

AI Coding Models Supported
AI Models Supported
AI Vision Models Supported
Foundation Models Supported
Multimodal Models Supported

Categories

AI Coding Models Supported
AI Models Supported
Foundation Models Supported
Multimodal Models Supported

Integrations

C Supported
C++ Supported
Cursor Supported
Doraverse Supported
Elixir Supported
HTML Supported
Java Supported
JavaScript Supported
Julia Supported
Kotlin Supported
LaunchLemonade Supported
OpenClaw Supported
PHP Supported
Python Supported
R Supported
Ruby Supported
SQL Supported
TypeScript Supported
Visual Basic Supported
Zo Computer Supported

Integrations

C Supported
C++ Supported
Cursor Supported
Doraverse Supported
Elixir Supported
HTML Supported
Java Supported
JavaScript Supported
Julia Supported
Kotlin Supported
LaunchLemonade Supported
OpenClaw Supported
PHP Supported
Python Supported
R Supported
Ruby Supported
SQL Supported
TypeScript Supported
Visual Basic Supported
Zo Computer Supported
Claim Claude Fable 5.5 and update features and information
Claim Claude Fable 5.5 and update features and information
Claim Grok 4.1 Fast and update features and information
Claim Grok 4.1 Fast and update features and information