What the official prompt archive is

The official system-prompt release-notes page covers Claude web and mobile app prompt updates. It says the prompt supplies information such as the current date and nudges certain behavior such as Markdown code snippets. It also says updates are periodic and do not apply to the API.

That means the page is a source for the product prompt record, not a universal statement about every Claude runtime, every Claude Code tool wrapper, or every partner deployment.

Published prompt entries

Model groupPublished prompt dates visible in docs
Claude Fable 5June 9, 2026
Claude Opus 4.8May 28, 2026
Claude Opus 4.7April 16, 2026
Claude Sonnet 4.6February 17, 2026
Claude Opus 4.6February 5, 2026
Claude Opus 4.5November 24, 2025; January 18, 2026
Claude Haiku 4.5October 15, 2025; November 19, 2025; January 18, 2026
Claude Sonnet 4.5September 29, 2025; November 19, 2025; January 18, 2026
Claude Sonnet 3.5July 12, 2024; September 9, 2024; October 22, 2024; November 22, 2024

Why prompt history matters

Published prompts are behavioral artifacts. They show how Anthropic describes product capabilities, safety posture, available tools, and response style at a point in time. For researchers, those dates are useful even when the model weights are unavailable.

The prompt archive also helps avoid overclaiming. If a change is recorded as a Claude web or mobile app system-prompt change, do not cite it as an API behavior change unless the API docs independently say so.

What this page excludes

Claude Archive does not treat prompt-leak repositories as primary sources. It also does not reproduce full prompt text. The archival value here is the official publication trail, the dated model entries, and the scope caveats that keep downstream claims accurate.

Questions this page answers

Does the official Claude system-prompt page apply to the API?

No. The official page says those system-prompt updates do not apply to the Claude API.

When do the earliest visible official system-prompt entries start?

The current official page lists July 12, 2024 entries for Claude Sonnet 3.5, Opus 3, and Haiku 3.

Does Claude Archive publish leaked prompts?

No. Claude Archive cites Anthropic-published prompt release notes and avoids leaked or unofficial prompt repositories.