diff --git a/server/src/session/claude.rs b/server/src/session/claude.rs
index 79d89f5..ba4279c 100644
--- a/server/src/session/claude.rs
+++ b/server/src/session/claude.rs
@@ -192,14 +192,19 @@ const STDERR_LOG: &str = "stderr.log";
 /// they left behind, one ordinary request ("can you make it so you can
 /// rename a session?") cost 4.2 million tokens across its 130 calls.
 ///
-/// 100k is the smallest window the CLI accepts and roughly the cheapest:
-/// per-call cost falls with the cap, while the compaction it forces costs
-/// about the same in total either way -- a smaller window compacts more
-/// often but each pass is proportionally smaller. What it trades is how
-/// much detail survives a compaction, which is a real cost to the work
-/// and the reason this is one named constant rather than a computed
-/// value. Raise it if sessions start losing the thread.
-const AUTOCOMPACT_WINDOW: &str = "100k";
+/// 200k rather than the 100k floor, because the cheapest window on tokens
+/// is not the best one to sit in front of. Measured on the same session:
+/// context comes back to 70-85k within ten calls of a compaction, so a
+/// 100k window compacts about every thirteen calls, and a compaction
+/// takes roughly two minutes (`durationMs` 104,346 to 147,671 across the
+/// six recorded). A 130-call request would spend some twenty minutes
+/// compacting. 200k keeps most of the saving against the 1M ceiling and
+/// halves the stalls.
+///
+/// Worth knowing before tuning this: the window decides how often the
+/// context is thrown away, not how fast it fills. What fills it is ~7k
+/// per call of tool output, and no value here touches that.
+const AUTOCOMPACT_WINDOW: &str = "200k";
 
 /// How often a reader with nothing to read looks again.
 ///