For API apps, cap history at the last N turns and put unchanging instructions first so prompt caching can discount the prefix.
Build a Sliding Window with a Cached, Stable Prefix
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More in Context Management
🧠Context Management
Images can be 1,000-2,000+ tokens each; removing stale ones cuts that per turn
Drop the Screenshot Once the Model Has Read It
Images, PDFs, and attachments are charged as tokens and re-sent every turn in a multimodal thread. After the model has described or transcribed one, you usually don't need to keep sending the pixels.
🧠Context Management
50-90% on file-heavy prompts
Paste the Function, Not the Whole File
Most coding questions need 20-40 lines, not your 800-line file. Send the relevant slice plus a one-line note about the rest, and your input shrinks dramatically without hurting the answer.
🧠Context Management
Trims re-sent history; often 20-60% fewer input tokens per turn after a topic switch
Start a New Chat When the Topic Changes
Chat apps re-send your whole conversation with every message. When you switch tasks, the old turns become dead weight you keep paying to re-transmit — even with caching discounts.