diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2ab704d..3176285 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ and adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ### Fixes
 
+- On Windows, a console window no longer briefly flashes when CodeGraph runs as a background MCP server. When the npm launcher started the bundled runtime — which happens every time an editor starts the server or reconnects after the daemon idles out — and during its self-heal step that extracts a missing platform bundle, Windows would pop up a black console (conhost) window for a moment. Both now launch hidden, matching how the daemon already behaved; the browser-open step of `codegraph login` was hardened the same way. Thanks @luoyerr for the report and root-cause analysis. (#1092)
 - C++ forward declarations no longer crowd out the real class definition. A `class Foo;` forward declaration — common in large C++ and Unreal Engine codebases, where a heavily used class is forward-declared across dozens of headers — was indexed as its own class node every time it appeared. So exploring that class returned mostly forward-declaration sites, and could even pick one of them as the representative for blast-radius, burying the actual definition and its members and callers. Bodiless forward declarations are now skipped for C and C++, exactly as forward-declared structs and enums already were, so only the real definition is indexed. Languages where a class with no body is a complete definition — such as Kotlin's `class Empty` and Scala — are unaffected. Thanks @luoyxy for the report and root-cause analysis. (#1093)
 - C++ methods that return a reference, and user-defined conversion operators, are now indexed under their correct names. An inline getter like `const FGameplayTagContainer& GetActiveTags() const` — everywhere in Unreal Engine headers — was indexed as `& GetActiveTags() const` instead of `GetActiveTags`, and a conversion operator like `operator EALSMovementState() const` kept its trailing `() const` instead of reading `operator EALSMovementState`. In both cases the garbled name meant you couldn't find the symbol by name and its callers weren't linked. Both now read cleanly, matching how pointer-returning and value-returning methods already worked. (#1096)
 - C++ functions written with an inline-specifier macro before the return type are now indexed correctly. In Unreal Engine, inline helpers are commonly written `FORCEINLINE FString GetEnumerationToString(...)`; the `FORCEINLINE` macro made the parser read the return type as part of the function's name (`FString GetEnumerationToString` instead of `GetEnumerationToString`) and lose the real return type, so the function couldn't be found by name and its callers weren't linked. CodeGraph now recognizes the standard Unreal inline macros (`FORCEINLINE`, `FORCENOINLINE`, `FORCEINLINE_DEBUGGABLE`), so both the name and the return type are captured. (#1100)
diff --git a/__tests__/npm-shim.test.ts b/__tests__/npm-shim.test.ts
index bcb109f..39e7f91 100644
--- a/__tests__/npm-shim.test.ts
+++ b/__tests__/npm-shim.test.ts
@@ -71,6 +71,23 @@ function runShim(pkgDir: string, args: string[], env: Record<string, string>) {
   });
 }
 
+// Static source guard (all platforms): every child spawn in the shim must set
+// windowsHide, or a console (conhost) window flashes when the shim runs as a
+// background MCP server on Windows (issue #1092). windowsHide is a Windows-only
+// spawn behavior that can't be observed from these POSIX-only subprocess tests,
+// so we assert it at the source level instead — and this also catches any new
+// spawn site added to the shim later.
+describe('npm-shim windowsHide (#1092)', () => {
+  it('sets windowsHide: true on every spawn in the shim', () => {
+    const src = fs.readFileSync(SHIM_SRC, 'utf8');
+    const spawnLines = src.split('\n').filter((l) => /\.spawn(Sync)?\(/.test(l));
+    expect(spawnLines.length).toBeGreaterThan(0); // guard against a false pass if the calls move
+    for (const line of spawnLines) {
+      expect(line, `spawn without windowsHide: ${line.trim()}`).toContain('windowsHide: true');
+    }
+  });
+});
+
 describe.skipIf(isWindows)('npm-shim launcher', () => {
   it('runs the installed optional-dependency bundle without any download', async () => {
     const pkg = makePkg();
diff --git a/scripts/npm-shim.js b/scripts/npm-shim.js
index 8a756f5..3f2c2f3 100755
--- a/scripts/npm-shim.js
+++ b/scripts/npm-shim.js
@@ -45,7 +45,7 @@ async function main() {
   // Happy path: the npm-installed optional dependency. Fall back to a download
   // when the registry didn't deliver it.
   var resolved = resolveInstalledBundle() || (await selfHealBundle());
-  var res = childProcess.spawnSync(resolved.command, resolved.args, { stdio: 'inherit' });
+  var res = childProcess.spawnSync(resolved.command, resolved.args, { stdio: 'inherit', windowsHide: true });
   if (res.error) {
     process.stderr.write('codegraph: ' + res.error.message + '\n');
     process.exit(1);
@@ -222,7 +222,7 @@ function extract(archive, destDir) {
   var args = isWindows
     ? ['-xf', archive, '-C', destDir, '--strip-components=1']
     : ['-xzf', archive, '-C', destDir, '--strip-components=1'];
-  var res = childProcess.spawnSync('tar', args, { stdio: 'ignore' });
+  var res = childProcess.spawnSync('tar', args, { stdio: 'ignore', windowsHide: true });
   if (res.error) throw new Error('tar unavailable: ' + res.error.message);
   if (res.status !== 0) throw new Error('tar exited ' + res.status);
 }
diff --git a/src/reasoning/login.ts b/src/reasoning/login.ts
index 15061fa..70faf18 100644
--- a/src/reasoning/login.ts
+++ b/src/reasoning/login.ts
@@ -80,7 +80,7 @@ export async function openBrowser(url: string): Promise<void> {
     : process.platform === 'win32' ? ['cmd', ['/c', 'start', '', url]]
     : ['xdg-open', [url]];
   try {
-    const child = spawn(cmd as string, args as string[], { stdio: 'ignore', detached: true });
+    const child = spawn(cmd as string, args as string[], { stdio: 'ignore', detached: true, windowsHide: true });
     child.on('error', () => {});
     child.unref();
   } catch {
diff --git a/src/upgrade/index.ts b/src/upgrade/index.ts
index a949440..e98f5ff 100644
--- a/src/upgrade/index.ts
+++ b/src/upgrade/index.ts
@@ -546,7 +546,7 @@ export function hasCommand(cmd: string): boolean {
 }
 
 export function defaultRun(cmd: string, args: string[], env?: NodeJS.ProcessEnv): number {
-  const r = spawnSync(cmd, args, { stdio: 'inherit', env: env ?? process.env });
+  const r = spawnSync(cmd, args, { stdio: 'inherit', env: env ?? process.env, windowsHide: true });
   if (r.error) return -1;
   return r.status ?? -1;
 }