What is the difference between prompt caching, context caching, and prefill caching?
Prefill caching is the infrastructure primitive — storing the KV-cache of a computed prompt prefix so subsequent identical prefixes skip the compute. Prompt caching (Anthropic, OpenAI, Google) is the *billing* feature that exposes prefill caching to you and drops cached-input tokens to roughly 10% of list price. Context caching is Google's marketing term for the same billing feature on Gemini. Practical impact: identical system prompts and static context across an agent's many turns cost near-zero to re-send.
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Framework dimensions
Call this framework and its tools from your own agent via the Model Context Protocol (MCP) server. Works with Claude Desktop, Cursor, Zed, Continue, and the OpenAI Agents SDK.
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