From 49f62ac2d0323c51e2c5e3b5309692fd5719f76b Mon Sep 17 00:00:00 2001
From: wassname <1103714+wassname@users.noreply.github.com>
Date: Thu, 16 Apr 2026 13:09:01 +0800
Subject: [PATCH] feat: clearer overlap error with compress() syntax for valid
 ranges

---
 compress-tool.ts | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/compress-tool.ts b/compress-tool.ts
index 3078af0..6a26736 100644
--- a/compress-tool.ts
+++ b/compress-tool.ts
@@ -205,13 +205,12 @@ export function registerCompressTool(
             .join(', ')
 
           const gapInfo = gaps.length > 0
-            ? gaps.join('; ')
-            : 'None — all visible messages are covered by existing blocks'
+            ? gaps.map(g => `compress(${g.replace('..', ', ')})`).join('; ')
+            : 'none available — all visible messages are covered by existing blocks'
 
           throw new Error(
-            `Overlapping compression ranges are not supported. ` +
-            `New range (${startId}..${endId}) overlaps existing block(s): ${overlapInfo}. ` +
-            `Valid compressible ranges: ${gapInfo}`,
+            `You tried compress(${startId}, ${endId}) but this overlaps existing summaries: ${overlapInfo}. ` +
+            `Instead use: ${gapInfo}`,
           )
         }