Last updated: March 2026
Privacy Policy
prompt-caching runs entirely on your machine. No data leaves. No analytics on your prompts. No telemetry.
What this plugin processes
The plugin reads the messages, system prompts, and tool definitions you pass to its MCP tools in order to inject cache_control markers. It also accumulates token usage counters in memory to show you session savings.
- Message arrays passed to
optimize_messages - System prompts and tool definitions you include
- Token counts returned by the Anthropic API (input, output, cache reads)
What this plugin does NOT do
- Does not transmit any of your data to external servers
- Does not store anything to disk — session statistics live in memory only and are lost on restart
- Does not log, track, or analyze your prompts, code, or conversations
- Does not include analytics, telemetry, or crash reporting of any kind
- Does not read your files, environment variables, or system configuration beyond what you explicitly pass to a tool
Third-party services
This plugin itself has no third-party integrations. When you use it as part of an AI workflow, your messages are sent to the services your client is configured to use:
- Anthropic API — your messages are processed by Anthropic's infrastructure. See Anthropic's Privacy Policy.
- Your AI client (Claude Code, Cursor, Windsurf, etc.) — each has its own privacy policy.
Data residency
No data from this plugin leaves the machine it runs on. All processing is local and in-memory. When you stop the MCP server, all session data is gone.
Contact
Questions about this privacy policy? Open an issue on GitHub: