Backend
Cache-Aware Prompting
by tokencalculator
Structures prompts so provider prompt caching actually applies. Use in any repeated-prefix workload such as RAG, agents or chat.
Skill content
Prompt caching only helps when the prefix is byte-identical across requests. Most prompts break that accidentally. Structure every prompt as: 1. Stable system instructions, in a fixed order. 2. Stable reference material: documentation, schemas, examples. 3. Cache breakpoint. 4. Variable content: conversation history, the current query, retrieved chunks. Common cache breakers to remove from the prefix: timestamps, request ids, user names, randomised example ordering, and any dynamically generated preamble. Measure the cached-token fraction. If it is below 60 percent on a repeated-prefix workload, something dynamic is sitting above stable content.