AI Radar

Grok Code Fast 1

Retired · Language, Code, Reasoning

Grok Code Fast 1 is an xAI reasoning model for agentic coding, released on 28 August 2025 on the xAI API and, free for a limited time, through coding tools such as GitHub Copilot and Cursor. xAI says it built the model from scratch on a new architecture and trained it on programming content and real-world pull requests. It was retired from the API on 15 May 2026. [1] [2] [3] Primary source

Timeline of Grok Code Fast 1 →

Claims and evidence

  • Released Generally available on the xAI API and free for a limited time on launch-partner coding tools at announcement; xAI says it had quietly released the model under a codename the week before. Primary source[1]header; availability section
  • Retired Effective 12:00 PM PT on the xAI API. Primary source[3]first paragraph
  • Status RetiredRetired from the xAI API; requests to grok-code-fast-1 are served by grok-build-0.1. Primary source[3]list of retired models
      • Feature Tool useBuilt for agentic coding harnesses; xAI names tools such as grep, terminal and file editing. Primary source[1]A speedy daily driver [2]1 Introduction
      • Parameters Not disclosedNot disclosed by xAI. No claim madeNo source
      • Access APIAlso offered through third-party coding tools (GitHub Copilot, Cursor, Cline, Roo Code, Kilo Code, opencode, Windsurf); these are not cloud platforms, so they are not recorded as cloud-partner. Primary source[1]availability section [2]1 Introduction

      Lineage

      Predecessors

      No known predecessor.

      Successors

      No known successor.

      Based on

      Not derived from another model.

      Variants and derived

      None recorded.

      Siblings

      None recorded.

      All ancestors

      None.

      All descendants

      None.

      Variants

      No variants recorded in this record.

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