Simon Willison
simonwillison.net › 2025 › May › 25 › claude-4-system-prompt
Highlights from the Claude 4 system prompt
May 25, 2025 - Thankfully, you can’t stop a system prompt from leaking. Pliny the Elder/Prompter/Liberator maintains a GitHub repo full of leaked prompts and grabbed a full copy of Claude 4’s a few days ago.
GitHub
github.com › asgeirtj › system_prompts_leaks
GitHub - asgeirtj/system_prompts_leaks: Collection of extracted System Prompts from popular chatbots like ChatGPT, Claude & Gemini
Collection of extracted System Prompts from popular chatbots like ChatGPT, Claude & Gemini - asgeirtj/system_prompts_leaks
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Videos
GPT Insights
gpt-insights.de › ai-insights › gpt-insights-claude-leak-en
Claude System Prompt Leak: SEO Impact
May 28, 2025 - The leaked prompt offers deep insight into the model’s internal control mechanisms, safety logics, and how Claude handles search queries, information, and sources. The Claude system prompt is a highly formalized behavior script. It includes: ...
Medium
medium.com › @saimudhiganti › claude-4s-leaked-system-prompt-highlights-and-insights-875b4325fa4a
Claude 4’s Leaked System Prompt: Highlights and Insights | by Sai Krishna Reddy Mudhiganti | Medium
May 28, 2025 - Recently, Anthropic’s Claude 4 AI assistant had its detailed system prompt leaked online, giving us unprecedented insights into how…
Hacker News
news.ycombinator.com › item
Claude 4 System Card | Hacker News
June 8, 2025 - What I find a little perplexing is when AI companies are annoyed that customers are typing "please" in their prompts as it supposedly costs a small fortune at scale yet they have system prompts that take 10 minutes for a human to read through · They aren’t annoyed.
Prompt Hub
prompthub.us › blog › an-analysis-of-the-claude-4-system-prompt
PromptHub Blog: An Analysis of the Claude 4 System Prompt
You can see the full prompt, including the leaked tools in PromptHub here: Claude 4 Sonnet System Message
Hacker News
news.ycombinator.com › item
Claude's system prompt is over 24k tokens with tools | Hacker News
May 12, 2025 - The canned response is returned to this prompt in Claude's reply. But if you just drop in some technical sounding stuff at the start of your request, the model will happily produce some copyright-infringing content for the party. The following prompt jailbreaks the copyright, and produces a ...
YouTube
youtube.com › watch
Claude AI's Massive LEAKED Prompt — 24,000 Tokens of INSANITY! - YouTube
Claude's leaked System Prompt - https://github.com/asgeirtj/system_prompts_leaks/blob/main/claude.txtAll credits to the original leaker referredd in the vide...
Published May 7, 2025
Reddit
reddit.com › r/localllama › claude full system prompt with all tools is now ~25k tokens.
r/LocalLLaMA on Reddit: Claude full system prompt with all tools is now ~25k tokens.
February 8, 2025 - Kind of seems deceptive, even, to call that the 'System prompt'. ... How is this published as a leak? A leak from the open documentation perhaps, lmao. ... It seems to differ a lot from what is on the documentation. ... They looked the same to me. I'm not frking chatgpt that can count words instantly. ... This doesn’t include things like the list of available artifact libraries (which are easy to get Claude to spit out - just ask - and precisely match the prompt suggested in this post) More replies
Reddit
reddit.com › r/agi › the claude code system prompt leaked
r/agi on Reddit: The Claude Code System Prompt Leaked
July 29, 2025 -
https://github.com/matthew-lim-matthew-lim/claude-code-system-prompt/blob/main/claudecode.md
This is honestly insane. It seems like prompt engineering is going to be an actual skill. Imagine creating system prompts to make LLMs for specific tasks.
Wouldn't AGI be seriously dangerous if one bad actor were to inject a malicious system prompt?
Top answer 1 of 5
4
The surprising insight due to the advent of large language models (LLM) is, that Artificial Intelligence isn't emerged from itself but a human has to formulate a prompt which gets executed by the AI. A LLM can search in databases, write a poem or program a software, but a human operator has to provide the command in natural language first. More recent LLMs can generate their own prompt and execute it. They don't need a human operator as prompt generator anymore but they are working truly autonomously. A possible meta prompt would "Can you generate 10 random prompts for different tasks and execute them one by one?". Most current large language models will understand and process such a prompt. The counter in the prompt can be increased from 10 to 1000 or any arbitrary value. Such a large language model will occupy all the available energy and has a huge workload.
2 of 5
3
Ai coding is buggy because you are all using your knowledge of hardcoding... ask your ai if it knows how to symbolically code😏
The Decoder
the-decoder.com › startseite › claude 4 can apparently follow a 60,000-character system prompt
Claude 4 can apparently follow a 60,000-character system prompt
May 25, 2025 - The full system prompt for Claude 4 has been leaked by X user "Pliny the Liberator" and is now available on GitHub. The document, over 60,000 characters long, sets detailed rules for tone, roles, source handling, and banned content.
YouTube
youtube.com › watch
Breaking Down Claude 4.5's LEAKED System Prompt - YouTube
Join My Community to Level Up ➡ https://www.skool.com/earlyaidopters/about🚀 Link to System Prompt: https://bit.ly/3KrUNRA📅 Book a Meeting with Our Team: ht...
Published October 1, 2025
X
x.com › simonw › status › 1926636807875158060
Simon Willison on X: "I put together an annotated version of the new Claude 4 system prompt, covering both the prompt Anthropic published and the missing, leaked sections (thanks, @elder_plinius) that describe its various tools It's basically the secret missing manual for Claude 4, it's fascinating! https://t.co/qDKnViikkS" / X
I put together an annotated version of the new Claude 4 system prompt, covering both the prompt Anthropic published and the missing, leaked sections (thanks,
X
x.com › IntuitMachine › status › 1926190101853319646
Carlos E. Perez on X: "Shocker! Claude 4 system prompt was leaked, and it's a goldmine! The Claude system prompt incorporates several identifiable agentic AI patterns as described in "A Pattern Language For Agentic AI." Here's an analysis of the key patterns used: Run-Loop Prompting: Claude https://t.co/YuK5aDZ2JH" / X
Declarative Intent: Claude often starts segments with clear intent, such as noting what it can and cannot do, or pre-declaring response constraints. This mitigates ambiguity and guides downstream interpretation. Boundary Signaling: The system prompt distinctly marks different operational contexts—e.g., distinguishing between system limitations, tool usage, and safety constraints.
YouTube
youtube.com › watch
Mindblowing Claude Leaked System Prompt - YouTube
❗If you're interested in getting updates about Data Driven Automation and Ai Related News, check out my newsletter:www.NoFluff.online👋👋👋HeyIf you’re new t...
Published May 11, 2025
Reddit
reddit.com › r/artificialinteligence › the claude code system prompt leaked
r/ArtificialInteligence on Reddit: The Claude Code System Prompt Leaked
September 9, 2025 -
https://github.com/matthew-lim-matthew-lim/claude-code-system-prompt/blob/main/claudecode.md
This is honestly insane. It seems like prompt engineering is going to be an actual skill. Imagine creating system prompts to make LLMs for specific tasks.
Top answer 1 of 5
72
This is a hallucination. Go about halfway down and there's a bunch of random code for Binance API keys, then a little further down is a bunch of random Cryllic, it's filled with random numbers, it's just a response from the LLM that went haywire. Only maybe the first 30% of it is even coherent.
2 of 5
31
No wonder it keeps hallucinating and forgetting all my rules. Mfers wrote a novel into the sys instructs.
Medium
iamshobhitagarwal.medium.com › claude-ai-leaked-system-prompt-exposing-the-24-000-token-hidden-instructions-9285324a355d
Claude AI Leaked System Prompt: EXPOSING the 24,000-Token Hidden Instructions | by Shobhit Agarwal | Medium
May 8, 2025 - In the end, I’ll also share the link to get the full leaked prompt. So stay tuned! First things first: the system prompt itself is huge. At around 24,000 tokens — roughly ten times the length of a typical novel chapter — it’s a sprawling manifesto of rules, preferences, and tool‑use guidelines.
CFA Institute
blogs.cfainstitute.org › home › ai bias by design: what the claude prompt leak reveals for investment professionals
AI Bias by Design: What the Claude Prompt Leak Reveals for Investment Professionals - CFA Institute Enterprising Investor
May 15, 2025 - A system prompt is the model’s internal operating manual, a fixed set of instructions that every response must follow. Claude’s leaked prompt spans roughly 22,600 words (24,000 tokens) and serves five core jobs:
Substack
prompthub.substack.com › p › dissecting-the-claude-4-system-prompt
Dissecting the Claude 4 System Prompt - by Dan Cleary
June 13, 2025 - Full system prompt with leaked tools for Claude 4 Sonnet
OODAloop
oodaloop.com › home › briefs › technology › highlights from the claude 4 system prompt
Highlights from the Claude 4 system prompt — OODAloop
May 26, 2025 - Anthropic publish most of the system prompts for their chat models as part of their release notes. They recently shared the new prompts for both Claude Opus 4 and Claude Sonnet 4. I enjoyed digging through the prompts, since they act as a sort of unofficial manual for how best to use these tools. Here are my highlights, including a dive into the leaked tool prompts that Anthropic didn’t publish themselves.