Sweep 19 Sep 2026 · 02:36Z Build v2.1.278 500 read Stable v2.1.267 Latest v2.1.278 Next v2.1.278 Feeds RSS JSON llms.txt Unofficial
Claude Code v2.1.257 ·

systemPromptSnapshot option for records the system prompt once per conversation

A systemPromptSnapshot option freezes the system prompt for a conversation, so mid-session changes wait for compaction.

TierUse it nowhow much it should matter to you
Useful5my rating, 1 to 5
Signal4worth watching, 1 to 5
AreaSystem Promptwhat it touches
KindNew Featuresin v2.1.257,
Use it now Notable No documentation found

A systemPromptSnapshot option freezes the system prompt for a conversation, so mid-session changes wait for compaction.

A new systemPromptSnapshot option records a conversation's system prompt once and reuses it verbatim on every later request and resume, instead of re-rendering appendSystemPrompt each launch. When a snapshot exists, mid-session model switches or system-prompt changes only take effect after compaction or a new session.

Read from
Names in the bundlesystemPromptSnapshotappendSystemPrompt

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