diff --git a/crates/openshell-cli/src/run.rs b/crates/openshell-cli/src/run.rs
index 218d04e99..58411ba50 100644
--- a/crates/openshell-cli/src/run.rs
+++ b/crates/openshell-cli/src/run.rs
@@ -2455,13 +2455,6 @@ pub async fn sandbox_create(
     }
 }
 
-/// The default community sandbox registry prefix.
-///
-/// Bare sandbox names (e.g., `openclaw`) are expanded to
-/// `{prefix}/{name}:latest` using this value.  Override with the
-/// `OPENSHELL_COMMUNITY_REGISTRY` environment variable.
-const DEFAULT_COMMUNITY_REGISTRY: &str = "ghcr.io/nvidia/openshell-community/sandboxes";
-
 /// Resolved source for the `--from` flag on `sandbox create`.
 enum ResolvedSource {
     /// A ready-to-use container image reference.
@@ -2527,16 +2520,11 @@ fn resolve_from(value: &str) -> Result<ResolvedSource> {
         ));
     }
 
-    // 3. Looks like a full image reference (contains / : or .).
-    if value.contains('/') || value.contains(':') || value.contains('.') {
-        return Ok(ResolvedSource::Image(value.to_string()));
-    }
-
-    // 4. Community sandbox name.
-    let prefix = std::env::var("OPENSHELL_COMMUNITY_REGISTRY")
-        .unwrap_or_else(|_| DEFAULT_COMMUNITY_REGISTRY.to_string());
-    let prefix = prefix.trim_end_matches('/');
-    Ok(ResolvedSource::Image(format!("{prefix}/{value}:latest")))
+    // 3. Full image reference or community sandbox name — delegate to shared
+    //    resolution in openshell-core.
+    Ok(ResolvedSource::Image(
+        openshell_core::image::resolve_community_image(value),
+    ))
 }
 
 fn source_requests_gpu(source: &str) -> bool {
diff --git a/crates/openshell-core/src/image.rs b/crates/openshell-core/src/image.rs
new file mode 100644
index 000000000..ff10baaac
--- /dev/null
+++ b/crates/openshell-core/src/image.rs
@@ -0,0 +1,103 @@
+// SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+//! Shared image-name resolution for community sandbox images.
+//!
+//! Both the CLI and TUI need to expand bare sandbox names (e.g. `"base"`) into
+//! fully-qualified container image references. This module centralises that
+//! logic so every client resolves names identically.
+
+/// Default registry prefix for community sandbox images.
+///
+/// Bare sandbox names are expanded to `{prefix}/{name}:latest`.
+/// Override at runtime with the `OPENSHELL_COMMUNITY_REGISTRY` env var.
+pub const DEFAULT_COMMUNITY_REGISTRY: &str = "ghcr.io/nvidia/openshell-community/sandboxes";
+
+/// Resolve a user-supplied image string into a fully-qualified reference.
+///
+/// Resolution rules (applied in order):
+/// 1. If the value contains `/`, `:`, or `.` it is treated as a complete image
+///    reference and returned as-is.
+/// 2. Otherwise it is treated as a community sandbox name and expanded to
+///    `{registry}/{value}:latest` where `{registry}` defaults to
+///    [`DEFAULT_COMMUNITY_REGISTRY`] but can be overridden via the
+///    `OPENSHELL_COMMUNITY_REGISTRY` environment variable.
+///
+/// This function only handles image-name resolution. Dockerfile detection is
+/// the responsibility of the caller (e.g. the CLI's `resolve_from()`).
+pub fn resolve_community_image(value: &str) -> String {
+    // Already a fully-qualified reference.
+    if value.contains('/') || value.contains(':') || value.contains('.') {
+        return value.to_string();
+    }
+
+    // Community sandbox shorthand → expand with registry prefix.
+    let prefix = std::env::var("OPENSHELL_COMMUNITY_REGISTRY")
+        .unwrap_or_else(|_| DEFAULT_COMMUNITY_REGISTRY.to_string());
+    let prefix = prefix.trim_end_matches('/');
+    format!("{prefix}/{value}:latest")
+}
+
+#[cfg(test)]
+#[allow(unsafe_code)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn bare_name_expands_to_community_registry() {
+        let result = resolve_community_image("base");
+        assert_eq!(
+            result,
+            "ghcr.io/nvidia/openshell-community/sandboxes/base:latest"
+        );
+    }
+
+    #[test]
+    fn bare_name_with_env_override() {
+        // Use a temp env override. Safety: test-only, and these env-var tests
+        // are not run concurrently with other tests reading the same var.
+        let key = "OPENSHELL_COMMUNITY_REGISTRY";
+        let prev = std::env::var(key).ok();
+        // SAFETY: single-threaded test context; no other thread reads this var.
+        unsafe { std::env::set_var(key, "my-registry.example.com/sandboxes") };
+        let result = resolve_community_image("python");
+        assert_eq!(result, "my-registry.example.com/sandboxes/python:latest");
+        // Restore.
+        match prev {
+            Some(v) => unsafe { std::env::set_var(key, v) },
+            None => unsafe { std::env::remove_var(key) },
+        }
+    }
+
+    #[test]
+    fn full_reference_with_slash_passes_through() {
+        let input = "ghcr.io/myorg/myimage:v1";
+        assert_eq!(resolve_community_image(input), input);
+    }
+
+    #[test]
+    fn reference_with_colon_passes_through() {
+        let input = "myimage:latest";
+        assert_eq!(resolve_community_image(input), input);
+    }
+
+    #[test]
+    fn reference_with_dot_passes_through() {
+        let input = "registry.example.com";
+        assert_eq!(resolve_community_image(input), input);
+    }
+
+    #[test]
+    fn trailing_slash_in_env_is_trimmed() {
+        let key = "OPENSHELL_COMMUNITY_REGISTRY";
+        let prev = std::env::var(key).ok();
+        // SAFETY: single-threaded test context; no other thread reads this var.
+        unsafe { std::env::set_var(key, "my-registry.example.com/sandboxes/") };
+        let result = resolve_community_image("base");
+        assert_eq!(result, "my-registry.example.com/sandboxes/base:latest");
+        match prev {
+            Some(v) => unsafe { std::env::set_var(key, v) },
+            None => unsafe { std::env::remove_var(key) },
+        }
+    }
+}
diff --git a/crates/openshell-core/src/lib.rs b/crates/openshell-core/src/lib.rs
index c785b0742..5cb10f395 100644
--- a/crates/openshell-core/src/lib.rs
+++ b/crates/openshell-core/src/lib.rs
@@ -12,6 +12,7 @@
 pub mod config;
 pub mod error;
 pub mod forward;
+pub mod image;
 pub mod inference;
 pub mod paths;
 pub mod proto;
diff --git a/crates/openshell-tui/src/lib.rs b/crates/openshell-tui/src/lib.rs
index e8759999a..f187f59fb 100644
--- a/crates/openshell-tui/src/lib.rs
+++ b/crates/openshell-tui/src/lib.rs
@@ -1274,8 +1274,9 @@ fn spawn_create_sandbox(app: &mut App, tx: mpsc::UnboundedSender<Event>) {
     tokio::spawn(async move {
         let has_custom_image = !image.is_empty();
         let template = if has_custom_image {
+            let resolved = openshell_core::image::resolve_community_image(&image);
             Some(openshell_core::proto::SandboxTemplate {
-                image,
+                image: resolved,
                 ..Default::default()
             })
         } else {