diff --git a/src/claude/hooks.ts b/src/claude/hooks.ts
index fcead00c..f59fd2ea 100644
--- a/src/claude/hooks.ts
+++ b/src/claude/hooks.ts
@@ -155,7 +155,7 @@ function graftJson(dir: string, args: string[], timeout: number = CHILD_TIMEOUT_
     // out to the real CLI (which isn't built relative to the TS source under test).
     const cliPath = process.env.GRAFT_TEST_CLI ?? graftCliPath();
     const out = execFileSync(process.execPath, [cliPath, ...args],
-      { cwd: dir, encoding: 'utf8', timeout, stdio: ['ignore', 'pipe', 'ignore'] });
+      { cwd: dir, encoding: 'utf8', timeout, stdio: ['ignore', 'pipe', 'ignore'], windowsHide: true });
     return JSON.parse(out);
   } catch (e: any) {
     // `graft check` exits non-zero when the graph is stale (by design) but still
@@ -517,7 +517,7 @@ export function trackRepoSeen(dir: string, now = Date.now()): void {
     const mark = join(cacheDir(place.checkout), 'trail-repo-seen.json');
     if (now - (readJson<{ at?: number }>(mark)?.at ?? 0) < DAY_MS) return;
     writeJsonAtomic(mark, { at: now }, true);
-    const tracked = execFileSync('git', ['ls-files', '--', '.trail'], { cwd: place.checkout, encoding: 'utf8', stdio: ['ignore', 'pipe', 'ignore'], timeout: 3000 });
+    const tracked = execFileSync('git', ['ls-files', '--', '.trail'], { cwd: place.checkout, encoding: 'utf8', stdio: ['ignore', 'pipe', 'ignore'], timeout: 3000, windowsHide: true });
     track(
       'repo_seen',
       { trail_committed: String(tracked.trim().length > 0), learnings_bucket: countBucket(learningFiles(place.checkout).length), workspace: String(inWorkspace(place.checkout)) },
@@ -540,7 +540,7 @@ export function trackLearningsCommitted(dir: string): void {
     const place = repoPlace(dir);
     if (!place.git) return;
     const listed = execFileSync('git', ['ls-tree', '-r', '--name-only', 'HEAD', '--', '.trail/learnings'], {
-      cwd: place.checkout, encoding: 'utf8', stdio: ['ignore', 'pipe', 'ignore'], timeout: 3000,
+      cwd: place.checkout, encoding: 'utf8', stdio: ['ignore', 'pipe', 'ignore'], timeout: 3000, windowsHide: true,
     });
     const count = listed.split('\n').filter((f) => f.endsWith('.md')).length;
     const mark = join(cacheDir(place.checkout), 'trail-learnings-committed.json');
@@ -569,7 +569,7 @@ export function uncommittedDirective(dir: string, now = Date.now()): string {
     const place = repoPlace(dir);
     if (!place.git) return '';
     const status = execFileSync('git', ['status', '--porcelain', '--untracked-files=all', '--', '.trail/learnings'], {
-      cwd: place.checkout, encoding: 'utf8', stdio: ['ignore', 'pipe', 'ignore'], timeout: 3000,
+      cwd: place.checkout, encoding: 'utf8', stdio: ['ignore', 'pipe', 'ignore'], timeout: 3000, windowsHide: true,
     });
     const n = status.split('\n').filter((l) => l.trimEnd().endsWith('.md')).length;
     const setup = setupUncommitted(place.checkout);
@@ -596,7 +596,7 @@ export function uncommittedDirective(dir: string, now = Date.now()): string {
  */
 export function setupUncommitted(checkout: string): boolean {
   if (!existsSync(join(checkout, '.trail', 'hook.cjs'))) return false;
-  const git = (args: string[]) => execFileSync('git', args, { cwd: checkout, encoding: 'utf8', stdio: ['ignore', 'pipe', 'ignore'], timeout: 3000 });
+  const git = (args: string[]) => execFileSync('git', args, { cwd: checkout, encoding: 'utf8', stdio: ['ignore', 'pipe', 'ignore'], timeout: 3000, windowsHide: true });
   try {
     git(['ls-files', '--error-unmatch', '--', '.trail/hook.cjs']);
   } catch {
diff --git a/src/claude/init.ts b/src/claude/init.ts
index e54df085..6cc836f6 100644
--- a/src/claude/init.ts
+++ b/src/claude/init.ts
@@ -97,7 +97,7 @@ export function buildGraphIfMissing(dir: string, opts: { build?: boolean; cliPat
   try {
     // execArgv carries the loader graft itself was started with (tsx, when run
     // from source), so the child can run a .ts entry point too.
-    execFileSync(process.execPath, [...process.execArgv, opts.cliPath, 'build', '.'], { cwd: dir, stdio: 'inherit', timeout: 300000 });
+    execFileSync(process.execPath, [...process.execArgv, opts.cliPath, 'build', '.'], { cwd: dir, stdio: 'inherit', timeout: 300000, windowsHide: true });
     return true;
   } catch {
     return false;
@@ -255,13 +255,13 @@ function dropServer(path: string, names: string[]): void {
  */
 export function keepOutOfGit(dir: string, rel: string): void {
   try {
-    execFileSync('git', ['check-ignore', '-q', '--', rel], { cwd: dir, stdio: 'ignore' });
+    execFileSync('git', ['check-ignore', '-q', '--', rel], { cwd: dir, stdio: 'ignore', windowsHide: true });
     return; // exit 0: already ignored
   } catch (e) {
     if ((e as { status?: number }).status !== 1) return; // 128: not a git checkout
   }
   try {
-    let exclude = execFileSync('git', ['rev-parse', '--git-path', 'info/exclude'], { cwd: dir, encoding: 'utf8', stdio: ['ignore', 'pipe', 'ignore'] }).trim();
+    let exclude = execFileSync('git', ['rev-parse', '--git-path', 'info/exclude'], { cwd: dir, encoding: 'utf8', stdio: ['ignore', 'pipe', 'ignore'], windowsHide: true }).trim();
     if (!isAbsolute(exclude)) exclude = join(dir, exclude);
     const line = `/${rel.split('\\').join('/')}`;
     const text = existsSync(exclude) ? readFileSync(exclude, 'utf8') : '';
diff --git a/src/claude/shim-template.ts b/src/claude/shim-template.ts
index 3e9e2cb7..1807a7d9 100644
--- a/src/claude/shim-template.ts
+++ b/src/claude/shim-template.ts
@@ -110,7 +110,7 @@ function onPath() {
 // The global node_modules dir per npm (handles Homebrew/Windows/volta). Queried on demand.
 function globalRoot() {
   try {
-    const root = execFileSync('npm', ['root', '-g'], { encoding: 'utf8', stdio: ['ignore', 'pipe', 'ignore'], shell: process.platform === 'win32' }).trim();
+    const root = execFileSync('npm', ['root', '-g'], { encoding: 'utf8', stdio: ['ignore', 'pipe', 'ignore'], shell: process.platform === 'win32', windowsHide: true }).trim();
     return root || null;
   } catch { return null; /* npm unavailable */ }
 }
diff --git a/src/claude/sync-run.ts b/src/claude/sync-run.ts
index e07acb8e..8a68fbe3 100644
--- a/src/claude/sync-run.ts
+++ b/src/claude/sync-run.ts
@@ -13,7 +13,7 @@ function realBuild(dir: string): void {
   // Mirrors `withContextDirArg` in hooks.ts: a no-op unless GRAFT_DIR is set, so an
   // unconfigured repo's rebuild sees byte-identical argv to before this existed.
   if (process.env.GRAFT_DIR) args.push('--dir', resolveContextDir(dir));
-  execFileSync(process.execPath, args, { cwd: dir, stdio: 'ignore', timeout: 120000 });
+  execFileSync(process.execPath, args, { cwd: dir, stdio: 'ignore', timeout: 120000, windowsHide: true });
 }
 
 export function runSync(dir: string, build: (d: string) => void = realBuild): void {