Mistral Medium 3.5

Overview

Mistral Medium 3.5 occupies the middle tier of Mistral AI's model lineup — delivering significantly more reasoning capability than Mistral Small while remaining more cost-efficient than the full Mistral Large. With a 262,000-token context window, it can process large technical documents, multi-file codebases, and lengthy dependency manifests in a single request.

Released in April 2026, Mistral Medium 3.5 is available through OpenRouter and is well-suited for engineering teams that need reliable, general-purpose language understanding at production scale without the overhead of a frontier model.

Key Capabilities

• 262k Token Context Window — analyse large codebases, dependency trees, and audit reports in a single pass
• Balanced Cost/Performance — strong reasoning at a lower price point than frontier models
• Long-Context Summarisation — distil lengthy changelogs, advisories, and technical documents
• Structured Output — reliable JSON and markdown generation for tool-integrated pipelines
• Instruction Following — precise adherence to complex prompts and structured templates

Use Cases for Engineering Teams

• Dependency Change Analysis — compare dependency manifests between releases and generate structured diff summaries
• Long-Document Reasoning — process complete technical specifications or audit reports to extract actionable insights
• Security Advisory Summarisation — ingest CVE reports and map them against project dependency lists
• Automated Release Notes — generate human-readable summaries from raw library changelogs
• RAG over Large Corpora — serve as the reasoning backbone for retrieval-augmented dependency knowledge bases

Technical Specifications

• Context Window: 262,144 tokens
• Pricing: Not publicly announced at launch
• Open Weight: No
• Release Date: 2026-04-30

Provider

Mistral Medium 3.5 is developed by Mistral AI. For the latest information, visit the OpenRouter listing.