Leaked Claude Opus 5 system prompt appears to span 200,000 characters
mcraddock · x · 2026-07-25
- A post claims to have leaked the full system prompt for Claude Opus 5, describing it as about 200,000 characters long.
- The screenshot highlights a new block called <fablesafeguardsrouting>.
- The prompt text also includes Anthropic product information, such as Claude being available in web, mobile, desktop, API, and other product surfaces.
- Because this is a purported system-prompt leak, it is mainly useful as a model-behavior and safety artifact rather than a standard product announcement.
Related event: Anthropic's Claude Opus 5 System Prompt Allegedly Leaked(2 posts)→
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