KalarisLabs/claude-systems-prompts

### A dated, exact archive of all official Anthropic system prompts for Claude, from Claude Fable 5.2 back to Claude Haiku 3.
Curated & Extracted by Sayan Chowdhury
All official Claude system prompts for claude.ai, the Claude iOS app, and the Claude Android app, plus original analysis of how Claude is engineered to think, refuse, write, and use tools.
Models at a Glance | Who This Is For | Key Revelations | Full Fable 5 Prompt | Analysis | Highlights
## The Prompts Are Public. Almost Nobody Reads Them.
Anthropic publishes Claude's system prompts on its own release notes pages. Twenty-three models worth, hiding in plain sight. And almost nobody reads them.
That should bother you. The system prompt decides what Claude refuses, how it formats your answer, when it searches the web, what it makes of your legal questions, and how it responds to a mental health crisis. It is the most underrated document in AI right now, and it is free to read.
This repo archives all of it. Every official prompt Anthropic ships for claude.ai and the Claude mobile apps, copied exactly, with dates and source links: Claude Fable 5.2 (November 9, 2026) back to Claude Haiku 3 (July 12, 2024). No paraphrase. No summaries. No "reportedly."
What is inside:
models/: all 23 official system prompts, copied exactly, with latest version dates, full version history per model, and direct links to the source page for every release
system-prompt/: deep dive on the flagship: the complete ~1,580-line Claude Fable 5 system prompt, tool definitions, and multi-part analysis
highlights/: the most surprising findings across the Claude prompt family
Coverage: 23 models. 50 published prompt versions referenced. July 2024 to November 2026. Every file copied exactly from Anthropic's own pages.
## Models at a Glance
All 23 official prompts, sorted by family and date. If a prompt is not on this table, it has not been published.
Every archived prompt lives at models/ /system-prompt.md. Each file carries its latest version date, lists every version Anthropic has published on that model's page (newest first), and links the canonical source. See the full index with per-model version history in models/README.md.
| Model | Latest version | Archived prompt | Source (Anthropic) |
| Claude Fable 5.2 | November 9, 2026 | system-prompt.md | platform.claude.com |
| Claude Haiku 5.5 | October 26, 2026 | system-prompt.md | platform.claude.com |
| Claude Sonnet 5.5 | October 27, 2026 | system-prompt.md | platform.claude.com |
| Claude Opus 5.5 | October 27, 2026 | system-prompt.md | platform.claude.com |
| Claude Fable 5.1 | October 30, 2026 | system-prompt.md | platform.claude.com |
| Claude Opus 5 | October 30, 2026 | system-prompt.md | platform.claude.com |
| Claude Sonnet 5 | October 30, 2026 | system-prompt.md | platform.claude.com |
| Claude Fable 5 | October 30, 2026 | system-prompt.md | platform.claude.com |
| Claude Opus 4.8 | October 30, 2026 | system-prompt.md | platform.claude.com |
| Claude Opus 4.7 | October 30, 2026 | system-prompt.md | platform.claude.com |
| Claude Sonnet 4.6 | October 14, 2026 | system-prompt.md | platform.claude.com |
| Claude Opus 4.6 | October 30, 2026 | system-prompt.md | platform.claude.com |