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Swapping the system prompt mid-session now applies from the next turn instead of waiting for compaction
What
When Claude Code's internal system prompt is replaced mid-session, the new prompt text now takes effect starting from the very next turn. Tool definitions already sent to the model in that session stay unchanged. Previously, the new prompt only took effect at the next compaction (the point where conversation history gets condensed), unless a systemPromptSnapshot setting was turned off.
Why
This makes system-prompt changes apply sooner and more predictably, rather than sitting unused until the next compaction happens to occur.
Names in the bundlesystemPromptSnapshot