diff --git a/crates/core/src/commands/common.rs b/crates/core/src/commands/common.rs
index 715bf7e..204feec 100644
--- a/crates/core/src/commands/common.rs
+++ b/crates/core/src/commands/common.rs
@@ -11,23 +11,13 @@ use crate::{
         CommandArguments, Either, WireCommandChip, builder::CommandStringBuilder, run_command,
         run_command_with_env,
     },
-    errors::{CommandError, HiveInitialisationError, HiveLibError},
+    errors::{CommandError, HiveInitialisationError, HiveLibError, get_common_copy_path_help},
     hive::{
         HiveLocation,
         node::{Context, Push, SharedTarget},
     },
 };
 
-fn get_common_copy_path_help(error: &CommandError) -> Option<String> {
-    if let CommandError::CommandFailed { logs, .. } = error
-        && (logs.contains("error: unexpected end-of-file"))
-    {
-        Some("wire requires the deploying user or wire binary cache is trusted on the remote server. if you're attempting to make that change, skip keys with --no-keys. please read https://wire.forall.systems/guides/keys for more information".to_string())
-    } else {
-        None
-    }
-}
-
 /// Pushes the path with the regular nix commands.
 pub async fn push(
     context: &Context,
diff --git a/crates/core/src/errors.rs b/crates/core/src/errors.rs
index 64cfb22..7753308 100644
--- a/crates/core/src/errors.rs
+++ b/crates/core/src/errors.rs
@@ -16,6 +16,40 @@ use crate::{
     hive::node::{Name, SwitchToConfigurationGoal},
 };
 
+/// Extracts the actual error message content used to determine whether a copy-path failure should have help text placed on it
+pub(crate) trait CopyPathHelpError {
+    fn copy_path_error_message(&self) -> Option<&str>;
+}
+
+impl CopyPathHelpError for NixDaemonClientError {
+    fn copy_path_error_message(&self) -> Option<&str> {
+        if let Self::NixDaemonOperationError { msg, .. } = self {
+            Some(msg)
+        } else {
+            None
+        }
+    }
+}
+
+impl CopyPathHelpError for CommandError {
+    fn copy_path_error_message(&self) -> Option<&str> {
+        if let Self::CommandFailed { logs, .. } = self {
+            Some(logs)
+        } else {
+            None
+        }
+    }
+}
+
+/// Shared help text for error mesasges.
+pub(crate) fn get_common_copy_path_help<E: CopyPathHelpError + ?Sized>(
+    error: &E,
+) -> Option<String> {
+    let msg = error.copy_path_error_message()?;
+    let needle = "error: unexpected end-of-file";
+    msg.contains(needle).then(|| "wire requires the deploying user or wire binary cache is trusted on the remote server. if you're attempting to make that change, skip keys with --no-keys. please read https://wire.forall.systems/guides/keys for more information".to_string())
+}
+
 #[derive(Debug, Diagnostic, Error)]
 pub enum KeyError {
     #[diagnostic(code(wire::key::File))]
@@ -324,3 +358,102 @@ impl From<StorePathError> for HiveLibError {
         Self::StorePath(e)
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::assert_matches;
+
+    const EXPECTED_HELP: &str = "wire requires the deploying user or wire binary cache is trusted on the remote server. if you're attempting to make that change, skip keys with --no-keys. please read https://wire.forall.systems/guides/keys for more information";
+
+    #[test]
+    fn daemon_error_with_eof_produces_help() {
+        let error = NixDaemonClientError::NixDaemonOperationError {
+            name: "copy".into(),
+            msg: "error: unexpected end-of-file".into(),
+        };
+
+        assert_eq!(
+            get_common_copy_path_help(&error).as_deref(),
+            Some(EXPECTED_HELP)
+        );
+    }
+
+    #[test]
+    fn command_error_with_eof_produces_help() {
+        let error = CommandError::CommandFailed {
+            command_ran: "nix copy".into(),
+            logs: "info: something\nerror: unexpected end-of-file".into(),
+            code: "1".into(),
+            reason: "exit",
+        };
+
+        assert_eq!(
+            get_common_copy_path_help(&error).as_deref(),
+            Some(EXPECTED_HELP)
+        );
+    }
+
+    #[test]
+    fn daemon_error_message_extraction() {
+        let error = NixDaemonClientError::NixDaemonOperationError {
+            name: "query".into(),
+            msg: "unrelated".into(),
+        };
+        assert_eq!(
+            CopyPathHelpError::copy_path_error_message(&error),
+            Some("unrelated")
+        );
+
+        let other = NixDaemonClientError::Sigint;
+        assert_eq!(CopyPathHelpError::copy_path_error_message(&other), None);
+    }
+
+    #[test]
+    fn command_error_message_extraction() {
+        let error = CommandError::CommandFailed {
+            command_ran: "nix copy".into(),
+            logs: "anything".into(),
+            code: "1".into(),
+            reason: "exit",
+        };
+        assert_eq!(
+            CopyPathHelpError::copy_path_error_message(&error),
+            Some("anything")
+        );
+
+        let other = CommandError::NoHandle;
+        assert_eq!(CopyPathHelpError::copy_path_error_message(&other), None);
+    }
+
+    #[test]
+    fn daemon_error_without_eof_returns_none() {
+        let error = NixDaemonClientError::NixDaemonOperationError {
+            name: "copy".into(),
+            msg: "some other failure".into(),
+        };
+
+        assert_matches!(get_common_copy_path_help(&error), None);
+    }
+
+    #[test]
+    fn command_error_without_eof_returns_none() {
+        let error = CommandError::CommandFailed {
+            command_ran: "nix copy".into(),
+            logs: "unrelated log output".into(),
+            code: "1".into(),
+            reason: "exit",
+        };
+
+        assert_matches!(get_common_copy_path_help(&error), None);
+    }
+
+    #[test]
+    fn non_matching_error_variants_return_none() {
+        let daemon = NixDaemonClientError::Sigint;
+        assert_matches!(get_common_copy_path_help(&daemon), None);
+
+        let command = CommandError::NoHandle;
+        assert_matches!(get_common_copy_path_help(&command), None);
+    }
+}
diff --git a/crates/core/src/lib.rs b/crates/core/src/lib.rs
index 3eee9c1..1b23338 100644
--- a/crates/core/src/lib.rs
+++ b/crates/core/src/lib.rs
@@ -26,7 +26,7 @@ use wire_nix_client::{
 
 use crate::{
     commands::trace_nix_log_message,
-    errors::HiveLibError,
+    errors::{HiveLibError, get_common_copy_path_help},
     hive::node::{Context, Name, Push, SharedTarget},
     status::{UI_SENDER, UiMessage},
 };
@@ -159,16 +159,6 @@ where
     ))
 }
 
-fn get_common_copy_path_help(error: &NixDaemonClientError) -> Option<String> {
-    if let NixDaemonClientError::NixDaemonOperationError { msg, .. } = error
-        && (msg.contains("error: unexpected end-of-file"))
-    {
-        Some("wire requires the deploying user or wire binary cache is trusted on the remote server. if you're attempting to make that change, skip keys with --no-keys. please read https://wire.forall.systems/guides/keys for more information".to_string())
-    } else {
-        None
-    }
-}
-
 /// Pushes the path with a native daemon.
 pub async fn push_with_daemon(
     context: &Context,