From 145501d4a5e5a973b21c29b9b5806e2c4f153f9c Mon Sep 17 00:00:00 2001
From: "CJACK." <tetr20071102@gmail.com>
Date: Fri, 20 Mar 2026 01:15:32 +0800
Subject: [PATCH] fix(tool-sieve): allow mixed prose + tool json interception

---
 .../js/helpers/stream-tool-sieve/sieve.js     | 26 +++----------------
 tests/node/stream-tool-sieve.test.js          | 12 ++++-----
 2 files changed, 9 insertions(+), 29 deletions(-)

diff --git a/internal/js/helpers/stream-tool-sieve/sieve.js b/internal/js/helpers/stream-tool-sieve/sieve.js
index ef12e8b..ae95ffd 100644
--- a/internal/js/helpers/stream-tool-sieve/sieve.js
+++ b/internal/js/helpers/stream-tool-sieve/sieve.js
@@ -46,6 +46,9 @@ function processToolSieveChunk(state, chunk, toolNames) {
       if (Array.isArray(consumed.calls) && consumed.calls.length > 0) {
         state.pendingToolRaw = captured;
         state.pendingToolCalls = consumed.calls;
+        if (consumed.suffix) {
+          state.pending = consumed.suffix + state.pending;
+        }
         continue;
       }
       if (consumed.prefix) {
@@ -235,17 +238,6 @@ function consumeToolCapture(state, toolNames) {
     };
   }
 
-  // Strict standalone mode: if the stream already produced meaningful prose,
-  // treat later tool-looking JSON as plain text instead of intercepting.
-  if ((state.recentTextTail || '').trim() !== '' && prefixPart.trim() === '') {
-    return {
-      ready: true,
-      prefix: captured,
-      calls: [],
-      suffix: '',
-    };
-  }
-
   const parsed = parseStandaloneToolCallsDetailed(captured.slice(actualStart, obj.end), toolNames);
   if (!Array.isArray(parsed.calls) || parsed.calls.length === 0) {
     if (parsed.sawToolCallSyntax && parsed.rejectedByPolicy) {
@@ -264,18 +256,6 @@ function consumeToolCapture(state, toolNames) {
     };
   }
 
-  // Strict standalone mode: only intercept when the tool payload stands alone
-  // (allowing only surrounding whitespace). If there is non-whitespace prose
-  // before/after the JSON object, keep everything as normal text.
-  if (prefixPart.trim() !== '' || suffixPart.trim() !== '') {
-    return {
-      ready: true,
-      prefix: captured,
-      calls: [],
-      suffix: '',
-    };
-  }
-
   return {
     ready: true,
     prefix: prefixPart,
diff --git a/tests/node/stream-tool-sieve.test.js b/tests/node/stream-tool-sieve.test.js
index 61d72d6..7c703a1 100644
--- a/tests/node/stream-tool-sieve.test.js
+++ b/tests/node/stream-tool-sieve.test.js
@@ -259,28 +259,28 @@ test('sieve emits final tool_calls for split arguments payload without increment
   assert.deepEqual(finalCalls[0].input, { path: 'README.MD', mode: 'head' });
 });
 
-test('sieve keeps tool json as text when leading prose exists (strict mode)', () => {
+test('sieve still emits tool_calls when leading prose exists before tool json', () => {
   const events = runSieve(
     ['我将调用工具。', '{"tool_calls":[{"name":"read_file","input":{"path":"README.MD"}}]}'],
     ['read_file'],
   );
   const hasTool = events.some((evt) => (evt.type === 'tool_calls' && evt.calls?.length > 0) || (evt.type === 'tool_call_deltas' && evt.deltas?.length > 0));
   const leakedText = collectText(events);
-  assert.equal(hasTool, false);
+  assert.equal(hasTool, true);
   assert.equal(leakedText.includes('我将调用工具。'), true);
-  assert.equal(leakedText.toLowerCase().includes('tool_calls'), true);
+  assert.equal(leakedText.toLowerCase().includes('tool_calls'), false);
 });
 
-test('sieve keeps same-chunk trailing prose payload as text in strict mode', () => {
+test('sieve emits tool_calls and keeps trailing prose when payload and prose share a chunk', () => {
   const events = runSieve(
     ['{"tool_calls":[{"name":"read_file","input":{"path":"README.MD"}}]}然后继续解释。'],
     ['read_file'],
   );
   const hasTool = events.some((evt) => (evt.type === 'tool_calls' && evt.calls?.length > 0) || (evt.type === 'tool_call_deltas' && evt.deltas?.length > 0));
   const leakedText = collectText(events);
-  assert.equal(hasTool, false);
+  assert.equal(hasTool, true);
   assert.equal(leakedText.includes('然后继续解释。'), true);
-  assert.equal(leakedText.toLowerCase().includes('tool_calls'), true);
+  assert.equal(leakedText.toLowerCase().includes('tool_calls'), false);
 });
 
 test('formatOpenAIStreamToolCalls reuses ids with the same idStore', () => {