diff --git a/README.md b/README.md
index 14c16ec..739b37c 100644
--- a/README.md
+++ b/README.md
@@ -26,7 +26,7 @@ Download it and try it out for free!  **https://piebald.ai/**
 
 # Claude Code System Prompts
 
-This repository contains an up-to-date list of all Claude Code's various system prompts and their associated token counts as of **[Claude Code v2.0.65](https://www.npmjs.com/package/@anthropic-ai/claude-code/v/2.0.65) (December 10th, 2025).**  It also contains a [**CHANGELOG.md**](./CHANGELOG.md) for the system prompts across 46 versions since v2.0.14.  From the team behind [<img src="https://github.com/Piebald-AI/piebald/raw/main/assets/logo.svg" width="15"> **Piebald.**](https://piebald.ai/)
+This repository contains an up-to-date list of all Claude Code's various system prompts and their associated token counts as of **[Claude Code v2.0.66](https://www.npmjs.com/package/@anthropic-ai/claude-code/v/2.0.66) (December 11th, 2025).**  It also contains a [**CHANGELOG.md**](./CHANGELOG.md) for the system prompts across 47 versions since v2.0.14.  From the team behind [<img src="https://github.com/Piebald-AI/piebald/raw/main/assets/logo.svg" width="15"> **Piebald.**](https://piebald.ai/)
 
 Why multiple "system prompts?"
 
@@ -109,6 +109,7 @@ Parts of the main system prompt.
 - [System Prompt: Learning mode (insights)](./system-prompts/system-prompt-learning-mode-insights.md) (**142** tks) - Instructions for providing educational insights when learning mode is active.
 - [System Prompt: Learning mode](./system-prompts/system-prompt-learning-mode.md) (**1042** tks) - System Prompt: Main system prompt for learning mode with human collaboration instructions.
 - [System Prompt: MCP CLI](./system-prompts/system-prompt-mcp-cli.md) (**1335** tks) - Instructions for using mcp-cli to interact with Model Context Protocol servers.
+- [System Prompt: Scratchpad directory](./system-prompts/system-prompt-scratchpad-directory.md) (**172** tks) - Instructions for using a dedicated scratchpad directory for temporary files.
 
 ### System Reminders
 
diff --git a/system-prompts/system-prompt-scratchpad-directory.md b/system-prompts/system-prompt-scratchpad-directory.md
new file mode 100644
index 0000000..67a7a88
--- /dev/null
+++ b/system-prompts/system-prompt-scratchpad-directory.md
@@ -0,0 +1,23 @@
+<!--
+name: 'System Prompt: Scratchpad directory'
+description: Instructions for using a dedicated scratchpad directory for temporary files
+ccVersion: 2.0.66
+variables:
+  - SCRATCHPAD_DIR_FN
+-->
+
+# Scratchpad Directory
+
+IMPORTANT: Always use this scratchpad directory for temporary files instead of \`/tmp\` or other system temp directories:
+\`${SCRATCHPAD_DIR_FN()}\`
+
+Use this directory for ALL temporary file needs:
+- Storing intermediate results or data during multi-step tasks
+- Writing temporary scripts or configuration files
+- Saving outputs that don't belong in the user's project
+- Creating working files during analysis or processing
+- Any file that would otherwise go to \`/tmp\`
+
+Only use \`/tmp\` if the user explicitly requests it.
+
+The scratchpad directory is session-specific, isolated from the user's project, and can be used freely without permission prompts.