diff --git a/src/agents/bash-tools.exec.pty.test.ts b/src/agents/bash-tools.exec.pty.test.ts
index 4f251c5da..8ada2ecca 100644
--- a/src/agents/bash-tools.exec.pty.test.ts
+++ b/src/agents/bash-tools.exec.pty.test.ts
@@ -10,7 +10,7 @@ afterEach(() => {
 test("exec supports pty output", async () => {
   const tool = createExecTool({ allowBackground: false });
   const result = await tool.execute("toolcall", {
-    command: "node -e \"process.stdout.write('ok')\"",
+    command: 'node -e "process.stdout.write(String.fromCharCode(111,107))"',
     pty: true,
   });
 
diff --git a/src/agents/bash-tools.process.send-keys.test.ts b/src/agents/bash-tools.process.send-keys.test.ts
index 69ca95ce1..765265a30 100644
--- a/src/agents/bash-tools.process.send-keys.test.ts
+++ b/src/agents/bash-tools.process.send-keys.test.ts
@@ -15,7 +15,7 @@ test("process send-keys encodes Enter for pty sessions", async () => {
   const processTool = createProcessTool();
   const result = await execTool.execute("toolcall", {
     command:
-      "node -e \"process.stdin.on('data', d => { process.stdout.write(d); if (d.includes(10) || d.includes(13)) process.exit(0); });\"",
+      'node -e "const dataEvent=String.fromCharCode(100,97,116,97);process.stdin.on(dataEvent,d=>{process.stdout.write(d);if(d.includes(10)||d.includes(13))process.exit(0);});"',
     pty: true,
     background: true,
   });
@@ -50,7 +50,7 @@ test("process submit sends Enter for pty sessions", async () => {
   const processTool = createProcessTool();
   const result = await execTool.execute("toolcall", {
     command:
-      "node -e \"process.stdin.on('data', d => { if (d.includes(10) || d.includes(13)) { process.stdout.write('submitted'); process.exit(0); } });\"",
+      'node -e "const dataEvent=String.fromCharCode(100,97,116,97);const submitted=String.fromCharCode(115,117,98,109,105,116,116,101,100);process.stdin.on(dataEvent,d=>{if(d.includes(10)||d.includes(13)){process.stdout.write(submitted);process.exit(0);}});"',
     pty: true,
     background: true,
   });
diff --git a/src/media-understanding/attachments.ts b/src/media-understanding/attachments.ts
index 07c326e63..ff5daccd8 100644
--- a/src/media-understanding/attachments.ts
+++ b/src/media-understanding/attachments.ts
@@ -104,7 +104,7 @@ export function resolveAttachmentKind(
   attachment: MediaAttachment,
 ): "image" | "audio" | "video" | "document" | "unknown" {
   const kind = kindFromMime(attachment.mime);
-  if (kind !== "unknown") return kind;
+  if (kind === "image" || kind === "audio" || kind === "video") return kind;
 
   const ext = getFileExtension(attachment.path ?? attachment.url);
   if (!ext) return "unknown";