diff --git a/Cargo.lock b/Cargo.lock
index 0faf03a..da6c1a9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -446,6 +446,16 @@ dependencies = [
  "ferese-layout",
 ]
 
+[[package]]
+name = "ferese-effects-probe"
+version = "0.1.0"
+dependencies = [
+ "ferese-protocols",
+ "tempfile",
+ "wayland-client",
+ "wayland-protocols-wlr",
+]
+
 [[package]]
 name = "ferese-ipc"
 version = "0.1.0"
diff --git a/Cargo.toml b/Cargo.toml
index 9dade15..d205210 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,6 +7,7 @@ members = [
     "crates/ferese-ipc",
     "crates/ferese-layout",
     "crates/ferese-protocols",
+    "tools/ferese-effects-probe",
     "tools/ferese-malformed-client",
 ]
 resolver = "3"
@@ -35,9 +36,11 @@ tracing = "0.1.41"
 tracing-subscriber = { version = "0.3.20", features = ["env-filter"] }
 serde = { version = "1.0.228", features = ["derive"] }
 serde_json = "1.0.145"
+tempfile = "3.23.0"
 toml = "0.9.7"
 xcursor = "0.3.11"
 wayland-backend = "0.3.17"
 wayland-client = "0.31.15"
 wayland-scanner = "0.31.11"
 wayland-server = "0.31.14"
+wayland-protocols-wlr = { version = "0.3.12", features = ["client"] }
diff --git a/tools/ferese-effects-probe/Cargo.toml b/tools/ferese-effects-probe/Cargo.toml
new file mode 100644
index 0000000..322b7c9
--- /dev/null
+++ b/tools/ferese-effects-probe/Cargo.toml
@@ -0,0 +1,12 @@
+[package]
+name = "ferese-effects-probe"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+rust-version.workspace = true
+
+[dependencies]
+ferese-protocols = { path = "../../crates/ferese-protocols", default-features = false, features = ["client"] }
+tempfile.workspace = true
+wayland-client.workspace = true
+wayland-protocols-wlr.workspace = true
diff --git a/tools/ferese-effects-probe/src/main.rs b/tools/ferese-effects-probe/src/main.rs
new file mode 100644
index 0000000..17592b0
--- /dev/null
+++ b/tools/ferese-effects-probe/src/main.rs
@@ -0,0 +1,231 @@
+use std::error::Error;
+use std::io::{Seek, SeekFrom, Write};
+use std::os::fd::AsFd;
+
+use ferese_protocols::effects::v1::client::{
+    ferese_effects_manager_v1::FereseEffectsManagerV1,
+    ferese_surface_effects_v1::{self, FereseSurfaceEffectsV1},
+};
+use wayland_client::{
+    Connection, Dispatch, QueueHandle, delegate_noop,
+    protocol::{wl_buffer, wl_compositor, wl_registry, wl_shm, wl_shm_pool, wl_surface},
+};
+use wayland_protocols_wlr::layer_shell::v1::client::{
+    zwlr_layer_shell_v1::{self, ZwlrLayerShellV1},
+    zwlr_layer_surface_v1::{self, ZwlrLayerSurfaceV1},
+};
+
+const WIDTH: u32 = 640;
+const HEIGHT: u32 = 64;
+
+fn main() -> Result<(), Box<dyn Error>> {
+    let connection = Connection::connect_to_env()?;
+    let mut queue = connection.new_event_queue();
+    let qh = queue.handle();
+    connection.display().get_registry(&qh, ());
+    let mut state = ProbeState::default();
+
+    while state.effects.is_none() || !state.configured {
+        queue.blocking_dispatch(&mut state)?;
+        state.try_initialize(&qh)?;
+        if state.closed {
+            return Err("layer surface was closed before its first configure".into());
+        }
+    }
+
+    let effects = state.effects.clone().expect("effects initialized");
+    let initial_configures = state.configure_count;
+    for role in [
+        ferese_surface_effects_v1::Role::PanelElevated,
+        ferese_surface_effects_v1::Role::Popover,
+        ferese_surface_effects_v1::Role::Menu,
+        ferese_surface_effects_v1::Role::Notification,
+        ferese_surface_effects_v1::Role::Hud,
+        ferese_surface_effects_v1::Role::Modal,
+        ferese_surface_effects_v1::Role::Panel,
+    ] {
+        effects.set_role(role);
+        queue.roundtrip(&mut state)?;
+        if state.configure_count != initial_configures {
+            return Err(format!("semantic role {role:?} changed layer geometry").into());
+        }
+    }
+    effects.clear_role();
+    queue.roundtrip(&mut state)?;
+    if state.configure_count != initial_configures {
+        return Err("clearing the semantic role changed layer geometry".into());
+    }
+
+    println!(
+        "PASS surface.panel and all semantic roles preserved {}x{} layer geometry",
+        state.width, state.height
+    );
+    Ok(())
+}
+
+#[derive(Default)]
+struct ProbeState {
+    compositor: Option<wl_compositor::WlCompositor>,
+    shm: Option<wl_shm::WlShm>,
+    layer_shell: Option<ZwlrLayerShellV1>,
+    effects_manager: Option<FereseEffectsManagerV1>,
+    surface: Option<wl_surface::WlSurface>,
+    layer_surface: Option<ZwlrLayerSurfaceV1>,
+    effects: Option<FereseSurfaceEffectsV1>,
+    buffer: Option<wl_buffer::WlBuffer>,
+    configured: bool,
+    closed: bool,
+    configure_count: u32,
+    width: u32,
+    height: u32,
+}
+
+impl ProbeState {
+    fn try_initialize(&mut self, qh: &QueueHandle<Self>) -> Result<(), Box<dyn Error>> {
+        if self.surface.is_some() {
+            return Ok(());
+        }
+        let (Some(compositor), Some(_shm), Some(layer_shell), Some(effects_manager)) = (
+            self.compositor.as_ref(),
+            self.shm.as_ref(),
+            self.layer_shell.as_ref(),
+            self.effects_manager.as_ref(),
+        ) else {
+            return Ok(());
+        };
+
+        let surface = compositor.create_surface(qh, ());
+        let layer_surface = layer_shell.get_layer_surface(
+            &surface,
+            None,
+            zwlr_layer_shell_v1::Layer::Top,
+            "ferese-effects-probe".to_owned(),
+            qh,
+            (),
+        );
+        layer_surface.set_anchor(
+            zwlr_layer_surface_v1::Anchor::Top
+                | zwlr_layer_surface_v1::Anchor::Left
+                | zwlr_layer_surface_v1::Anchor::Right,
+        );
+        layer_surface.set_size(WIDTH, HEIGHT);
+        layer_surface.set_exclusive_zone(HEIGHT as i32);
+
+        let effects = effects_manager.get_surface_effects(&surface, qh, ());
+        effects.set_role(ferese_surface_effects_v1::Role::Panel);
+
+        surface.commit();
+        self.surface = Some(surface);
+        self.layer_surface = Some(layer_surface);
+        self.effects = Some(effects);
+        Ok(())
+    }
+}
+
+fn create_buffer(
+    shm: &wl_shm::WlShm,
+    qh: &QueueHandle<ProbeState>,
+    width: u32,
+    height: u32,
+) -> Result<wl_buffer::WlBuffer, Box<dyn Error>> {
+    let stride = width * 4;
+    let size = stride * height;
+    let mut file = tempfile::tempfile()?;
+    file.set_len(u64::from(size))?;
+    let pixel = [0x28_u8, 0x24, 0x20, 0xd8];
+    for _ in 0..width * height {
+        file.write_all(&pixel)?;
+    }
+    file.seek(SeekFrom::Start(0))?;
+
+    let pool = shm.create_pool(file.as_fd(), size as i32, qh, ());
+    let buffer = pool.create_buffer(
+        0,
+        width as i32,
+        height as i32,
+        stride as i32,
+        wl_shm::Format::Argb8888,
+        qh,
+        (),
+    );
+    pool.destroy();
+    Ok(buffer)
+}
+
+impl Dispatch<wl_registry::WlRegistry, ()> for ProbeState {
+    fn event(
+        state: &mut Self,
+        registry: &wl_registry::WlRegistry,
+        event: wl_registry::Event,
+        _data: &(),
+        _connection: &Connection,
+        qh: &QueueHandle<Self>,
+    ) {
+        let wl_registry::Event::Global {
+            name,
+            interface,
+            version,
+        } = event
+        else {
+            return;
+        };
+
+        match interface.as_str() {
+            "wl_compositor" => state.compositor = Some(registry.bind(name, version.min(6), qh, ())),
+            "wl_shm" => state.shm = Some(registry.bind(name, 1, qh, ())),
+            "zwlr_layer_shell_v1" => {
+                state.layer_shell = Some(registry.bind(name, version.min(4), qh, ()))
+            }
+            "ferese_effects_manager_v1" => {
+                state.effects_manager = Some(registry.bind(name, 1, qh, ()))
+            }
+            _ => {}
+        }
+    }
+}
+
+impl Dispatch<ZwlrLayerSurfaceV1, ()> for ProbeState {
+    fn event(
+        state: &mut Self,
+        layer_surface: &ZwlrLayerSurfaceV1,
+        event: zwlr_layer_surface_v1::Event,
+        _data: &(),
+        _connection: &Connection,
+        qh: &QueueHandle<Self>,
+    ) {
+        match event {
+            zwlr_layer_surface_v1::Event::Configure {
+                serial,
+                width,
+                height,
+            } => {
+                layer_surface.ack_configure(serial);
+                state.configure_count = state.configure_count.saturating_add(1);
+                state.width = if width == 0 { WIDTH } else { width };
+                state.height = if height == 0 { HEIGHT } else { height };
+                if !state.configured {
+                    let surface = state.surface.clone().expect("surface initialized");
+                    let shm = state.shm.as_ref().expect("shm initialized");
+                    let buffer = create_buffer(shm, qh, state.width, state.height)
+                        .expect("create configured shared-memory buffer");
+                    surface.attach(Some(&buffer), 0, 0);
+                    surface.damage_buffer(0, 0, state.width as i32, state.height as i32);
+                    surface.commit();
+                    state.buffer = Some(buffer);
+                    state.configured = true;
+                }
+            }
+            zwlr_layer_surface_v1::Event::Closed => state.closed = true,
+            _ => {}
+        }
+    }
+}
+
+delegate_noop!(ProbeState: ignore wl_compositor::WlCompositor);
+delegate_noop!(ProbeState: ignore wl_shm::WlShm);
+delegate_noop!(ProbeState: ignore wl_shm_pool::WlShmPool);
+delegate_noop!(ProbeState: ignore wl_buffer::WlBuffer);
+delegate_noop!(ProbeState: ignore wl_surface::WlSurface);
+delegate_noop!(ProbeState: ignore ZwlrLayerShellV1);
+delegate_noop!(ProbeState: ignore FereseEffectsManagerV1);
+delegate_noop!(ProbeState: ignore FereseSurfaceEffectsV1);