diff --git a/hive-agent/src/todo_server.rs b/hive-agent/src/todo_server.rs
index e5b845dc..39ff323c 100644
--- a/hive-agent/src/todo_server.rs
+++ b/hive-agent/src/todo_server.rs
@@ -22,6 +22,7 @@
 //! existing best-effort JSON-line clients (they just change which socket
 //! they dial, not the payload).
 
+use std::os::unix::fs::PermissionsExt;
 use std::path::{Path, PathBuf};
 use std::sync::Arc;
 
@@ -125,6 +126,15 @@ pub async fn run(
 /// Bind a `UnixListener` at `path`, creating the parent dir and unlinking a
 /// stale socket left by a prior boot (which would otherwise block `bind`
 /// with `EADDRINUSE`).
+///
+/// The mode is set **here, at creation** — not corrected afterwards by
+/// whoever notices. `connect(2)` on a unix socket requires *write*
+/// permission, and `bind` leaves `0777 & ~umask` (typically `0755`), which
+/// silently excludes every uid but the harness's own. `hive-c0re` pushes
+/// todos in over this socket from the host, so that default locks it out.
+/// Same two lines the sibling `web.sock` has carried all along
+/// (`web_ui::serve`); access control is the containing directory's job, not
+/// the socket's.
 fn bind(path: &Path) -> Result<UnixListener> {
     if let Some(parent) = path.parent() {
         std::fs::create_dir_all(parent)
@@ -133,7 +143,11 @@ fn bind(path: &Path) -> Result<UnixListener> {
     if path.exists() {
         let _ = std::fs::remove_file(path);
     }
-    UnixListener::bind(path).with_context(|| format!("bind in-agent socket {}", path.display()))
+    let listener = UnixListener::bind(path)
+        .with_context(|| format!("bind in-agent socket {}", path.display()))?;
+    std::fs::set_permissions(path, std::fs::Permissions::from_mode(0o666))
+        .with_context(|| format!("set perms on in-agent socket {}", path.display()))?;
+    Ok(listener)
 }
 
 /// Handle one connection: read a single JSON request line, apply it to the