From f2ee18f033ef11005d0615ae6fc108e1b594828d Mon Sep 17 00:00:00 2001
From: jatmn <the@jat.mn>
Date: Mon, 6 Jul 2026 17:03:23 -0700
Subject: [PATCH 1/2] fix(compact): count string message content

---
 src/services/compact/microCompact.test.ts | 73 +++++++++++++++++++++++
 src/services/compact/microCompact.ts      |  5 ++
 2 files changed, 78 insertions(+)

diff --git a/src/services/compact/microCompact.test.ts b/src/services/compact/microCompact.test.ts
index f46b339104..d36b8461ca 100644
--- a/src/services/compact/microCompact.test.ts
+++ b/src/services/compact/microCompact.test.ts
@@ -175,3 +175,76 @@ describe('microCompact MCP tool compaction', () => {
     })
   })
 })
+
+describe('estimateMessageTokens coverage', () => {
+  test('counts tokens from string content user messages', async () => {
+    const { estimateMessageTokens } = await import('./microCompact.js')
+
+    // Real user messages from the session can have string content (plain user prompt)
+    const messages: Message[] = [
+      createUserMessage({
+        content:
+          'Hello world this is a long user prompt that needs compression because it is over the threshold',
+      }),
+      createAssistantMessage({
+        content: [
+          {
+            type: 'text',
+            text: 'Hi there! I am happy to help you with your request today',
+            citations: [],
+          },
+        ],
+      }),
+    ]
+
+    const total = estimateMessageTokens(messages)
+    // The string-content user message should be counted alongside normal blocks.
+    expect(total).toBeGreaterThan(0)
+  })
+
+  test('counts tokens across all block types including tool_result and tool_use', async () => {
+    const { estimateMessageTokens } = await import('./microCompact.js')
+
+    const msg = createUserMessage({
+      content: [
+        { type: 'tool_result' as const, tool_use_id: 't1', content: 'A'.repeat(5000) },
+      ],
+    })
+    const msgWithText = createUserMessage({
+      content: [
+        { type: 'text' as const, text: 'User query here' },
+      ],
+    })
+    const asstTool = createAssistantMessage({
+      content: [
+        {
+          type: 'tool_use' as const,
+          id: 't1',
+          name: 'Bash',
+          input: { command: 'ls -la' },
+        },
+      ],
+    })
+    const msgWithResultAndText = createUserMessage({
+      content: [
+        { type: 'tool_result' as const, tool_use_id: 't1', content: 'file output data' },
+        { type: 'text' as const, text: 'based on that output I think the answer is yes' },
+      ],
+    })
+
+    const messages: Message[] = [msg, msgWithText, asstTool, msgWithResultAndText]
+
+    const total = estimateMessageTokens(messages)
+
+    // Must be significantly > 0 (all blocks counted)
+    expect(total).toBeGreaterThan(100)
+
+    // Must be larger than the old reducer's estimate (only string+text blocks)
+    // Old reducer would only see text blocks: 'User query here' + 'based on that output...'
+    // It would miss 5000-chars tool_result, tool_use name+input
+    const oldReducerEstimate = Math.ceil(
+      (13 + 46) * (4 / 3), // 'User query here' (13) + 'based on that...' (~46)
+    )
+    expect(total).toBeGreaterThan(oldReducerEstimate * 2)
+  })
+})
diff --git a/src/services/compact/microCompact.ts b/src/services/compact/microCompact.ts
index eaa92eda97..84531d1c53 100644
--- a/src/services/compact/microCompact.ts
+++ b/src/services/compact/microCompact.ts
@@ -168,6 +168,11 @@ export function estimateMessageTokens(messages: Message[]): number {
       continue
     }
 
+    if (typeof message.message?.content === 'string') {
+      totalTokens += roughTokenCountEstimation(message.message.content)
+      continue
+    }
+
     if (!Array.isArray(message.message.content)) {
       continue
     }

From c4b9906b2878130613f50205555336a69b417ca3 Mon Sep 17 00:00:00 2001
From: jatmn <the@jat.mn>
Date: Mon, 6 Jul 2026 17:24:03 -0700
Subject: [PATCH 2/2] test(compact): assert string content token estimate

---
 src/services/compact/microCompact.test.ts | 23 ++++++-----------------
 1 file changed, 6 insertions(+), 17 deletions(-)

diff --git a/src/services/compact/microCompact.test.ts b/src/services/compact/microCompact.test.ts
index d36b8461ca..f4493973ee 100644
--- a/src/services/compact/microCompact.test.ts
+++ b/src/services/compact/microCompact.test.ts
@@ -181,25 +181,14 @@ describe('estimateMessageTokens coverage', () => {
     const { estimateMessageTokens } = await import('./microCompact.js')
 
     // Real user messages from the session can have string content (plain user prompt)
-    const messages: Message[] = [
-      createUserMessage({
-        content:
-          'Hello world this is a long user prompt that needs compression because it is over the threshold',
-      }),
-      createAssistantMessage({
-        content: [
-          {
-            type: 'text',
-            text: 'Hi there! I am happy to help you with your request today',
-            citations: [],
-          },
-        ],
-      }),
-    ]
+    const content =
+      'Hello world this is a long user prompt that needs compression because it is over the threshold'
+    const messages: Message[] = [createUserMessage({ content })]
 
     const total = estimateMessageTokens(messages)
-    // The string-content user message should be counted alongside normal blocks.
-    expect(total).toBeGreaterThan(0)
+    // The string-content user message should be counted on its own; the old
+    // implementation returned 0 because it skipped non-array content.
+    expect(total).toBe(Math.ceil(Math.round(content.length / 4) * (4 / 3)))
   })
 
   test('counts tokens across all block types including tool_result and tool_use', async () => {