Grok 4.20 Reasoning

LLM
xAI

Grok 4.20 Reasoning is built for complex problem-solving, thinking through problems step-by-step before responding. It supports a 2M token context, function calling, and structured outputs, with automatic reasoning requiring n

Context tokens

128,000

Output tokens

8,192

Released

Mar 9, 2026

Schema

Presence/frequency penalties, stop sequences, and log probabilities are not supported.

Schema documentation

Capabilities

Tool use
Structured output

Supported tools

  • Seclai Content Tools

    Inspect source documents connected to your account. Includes tools for loading full content, reading character ranges, searching within documents, viewing stats, and listing available content sources. When a source_connection_content_version_id is provided in agent run metadata it is used as the default. Otherwise the model can discover content via list_content_sources.

  • Seclai Knowledge Base

    Search your knowledge bases using semantic similarity. Includes search_knowledge_base and list_knowledge_bases. When a knowledge_base_id is provided in the prompt or agent run metadata it is used as the default. Otherwise the model can discover available knowledge bases at runtime.

  • Seclai Memory Banks

    Manage persistent memory across agent runs. Includes tools for listing memory banks, writing entries, searching memory via semantic similarity, and loading entries in chronological order. Supports two memory types: 'conversation' (speaker-attributed turns) and 'general' (freeform text). Use key to organize entries by topic, session, or user.

  • Seclai Web Tools

    Fetch web pages and search the web from within agent prompt calls. Includes seclai_web_fetch for retrieving page content in markdown, HTML, or plain text, and seclai_web_search for finding relevant pages with content snippets.

  • Web Search

    The Web Search tool enables Grok to search the web in real-time and browse web pages to find information. This allows the model to search the internet, access web pages, and extract relevant information to answer queries with up-to-date content.

  • X Search

    The X Search tool enables Grok to perform keyword search, semantic search, user search, and thread fetch on X (formerly Twitter). This allows the model to access real-time social media content, analyze posts, and gather insights from X's vast data.

Pricing

TypeCreditsUnits
Input26.60Credits per 1k tokens
Output79.80Credits per 1k tokens

Variants

No variants available for this model.

Try This Model

Write a prompt and experiment with Grok 4.20 Reasoning in the model experiments page. You can compare it with other models side by side.