AINewsnow

What a 275K-Character Claude Prompt Teaches Us About Building AI Agents

This story is from 2026-09-02. It is preserved in the archive; the latest stories are on the live feed.

A GitHub repository recently published what it describes as a runtime system prompt for Claude Fable 5.1. The file contains more than 275,000 characters of instructions related to tool use, web search, memory, copyright, safety policies, and interface behaviour. That naturally produced a dramatic h…

Read the full story at DEV Community — AI ↗

Timeline · 1 report

  1. 2026-09-02 07:23 · DEV Community — AI
    What a 275K-Character Claude Prompt Teaches Us About Building AI Agents

More stories

  1. AI's role in building AI surging? Anthropic says Claude now leads 26% of its R&D — Mint AI
  2. Claude, Anthropic’s AI model, is helping to develop the next version of itself — Fast Company AI
  3. we made a 27b model for creative writing. performs as good as claude fable 5, at a 40x cheaper price, open weights. — r/GeminiAI
  4. AI skills — r/AI_Agents
  5. Anthropic selects Accenture as first embedded evaluator to help implement Amodei's slowdown proposal — CNBC Technology
  6. Bolt Adds DeepSeek V4.1 Flash at 10x Cheaper Than V4 Pro — AlphaSignal
  7. OpenAI ‘ethically hacked’ with help of Anthropic’s Claude chatbot — The Guardian AI
  8. How To Use Ai and create those videos — r/aivideo

Get the daily brief of stories like this at 6:30 every morning →