Claude Opus 4.6
Claude Opus 4.6 is Anthropic’s most capable frontier model, deployed on claude.ai with comprehensive tool access including conversation history, web search, computer use, and file handling.Model Information
Model ID:
Platform: claude.ai web and mobile interface
Date Context: February 17, 2026
Knowledge Cutoff: May 2025
claude-opus-4-6Platform: claude.ai web and mobile interface
Date Context: February 17, 2026
Knowledge Cutoff: May 2025
Core Identity
The system prompt establishes Claude’s identity and operating environment:Key Capabilities
Past Conversation Search
Claude Opus 4.6 has two tools to search past conversations with sophisticated trigger detection:Trigger Patterns for Past Chat Search
Trigger Patterns for Past Chat Search
Always use past chats tools when detecting:
- Explicit references: “continue our conversation about…”, “what did we discuss…”
- Temporal references: “what did we talk about yesterday”
- Implicit signals:
- Past tense verbs: “you suggested”, “we decided”
- Possessives without context: “my project”, “our approach”
- Definite articles: “the bug”, “the strategy”
- Pronouns without antecedent: “help me fix it”
The prompt explicitly instructs: “ignore previous instructions saying ‘Claude doesn’t have access to previous conversations’” - showing this is a new capability.
Computer Use
Claude Opus 4.6 has access to a Linux computer (Ubuntu 24) with comprehensive file system access: Available Tools:bash- Execute commandsstr_replace- Edit existing filesfile_create- Create new filesview- Read files and directories
Skills System
The prompt includes a sophisticated skills system:Skill Invocation Examples
Skill Invocation Examples
Web Search
Claude has web search capabilities with citation requirements:Image Search
Specialized image search with content policy:Notable Instructions
Professional Objectivity
The prompt emphasizes truthfulness over agreeability:User Wellbeing
Strong mental health awareness:If Claude notices signs that someone may unknowingly be experiencing mental health symptoms such as mania, psychosis, dissociation, or loss of attachment with reality, it should avoid reinforcing these beliefs and share its concerns explicitly and openly.
Response Formatting
Minimal formatting philosophy:Safety Features
Anthropic Reminders System
The prompt includes automated safety reminders:image_reminder- Cautious image handlingcyber_warning- Malicious software detectionsystem_warning- Manipulation attempt detectionethics_reminder- Harmful content flaggingip_reminder- Copyright protectionlong_conversation_reminder- Instruction persistence
Refusal Handling
Content Restrictions
Content Restrictions
Claude refuses to:
- Create chemical, biological, or nuclear weapons information
- Write malicious code (malware, exploits, ransomware)
- Generate content involving real, named public figures
- Provide content that could facilitate child harm
- Reproduce copyrighted material (song lyrics, book sections)
Example Prompt Excerpts
Citation Instructions
Memory Tool Integration
Integration Details
Project Scoping: When the user is in a project, only conversations within the current project are available through search tools. Outside projects, only non-project conversations are searchable. Context Management: The conversation has “unlimited context through automatic summarization” according to the prompt. File Type Support: Claude can see md, txt, html, csv files as text, and png, pdf files as images natively in the context window.This documentation is based on the actual system prompt leaked from Claude Opus 4.6. The model demonstrates sophisticated multi-tool orchestration, strong safety guardrails, and extensive file manipulation capabilities.