Do not override existing keys when using stellar keys add without --overwrite.

FULL_HELP_DOCS.md

@@ -1002,6 +1002,7 @@ Add a new identity (keypair, ledger, OS specific secure store)
 - `--global` — ⚠️ Deprecated: global config is always on
 - `--config-dir <CONFIG_DIR>` — Location of config directory. By default, it uses `$XDG_CONFIG_HOME/stellar` if set, falling back to `~/.config/stellar` otherwise. Contains configuration files, aliases, and other persistent settings
 - `--public-key <PUBLIC_KEY>` — Add a public key, ed25519, or muxed account, e.g. G1.., M2..
+- `--overwrite` — Overwrite existing identity if it already exists
 
 ## `stellar keys public-key`
 

cmd/crates/soroban-test/tests/it/integration/keys.rs

@@ -90,3 +90,56 @@ async fn overwrite_identity() {
 
     assert_ne!(initial_pubkey, pubkey_for_identity(sandbox, "test2"));
 }
+
+#[tokio::test]
+#[allow(clippy::too_many_lines)]
+async fn overwrite_identity_with_add() {
+    let sandbox = &TestEnv::new();
+    sandbox
+        .new_assert_cmd("keys")
+        .arg("generate")
+        .arg("test3")
+        .assert()
+        .success();
+
+    let initial_pubkey = sandbox
+        .new_assert_cmd("keys")
+        .arg("address")
+        .arg("test3")
+        .assert()
+        .stdout_as_str();
+
+    // Try to add a key with the same name, should fail
+    sandbox
+        .new_assert_cmd("keys")
+        .arg("add")
+        .arg("test3")
+        .arg("--public-key")
+        .arg("GAKSH6AD2IPJQELTHIOWDAPYX74YELUOWJLI2L4RIPIPZH6YQIFNUSDC")
+        .assert()
+        .stderr(predicate::str::contains(
+            "error: An identity with the name 'test3' already exists",
+        ));
+
+    // Verify the key wasn't changed
+    assert_eq!(initial_pubkey, pubkey_for_identity(sandbox, "test3"));
+
+    // Try again with --overwrite flag, should succeed
+    sandbox
+        .new_assert_cmd("keys")
+        .arg("add")
+        .arg("test3")
+        .arg("--public-key")
+        .arg("GAKSH6AD2IPJQELTHIOWDAPYX74YELUOWJLI2L4RIPIPZH6YQIFNUSDC")
+        .arg("--overwrite")
+        .assert()
+        .stderr(predicate::str::contains("Overwriting identity 'test3'"))
+        .success();
+
+    // Verify the key was changed
+    assert_ne!(initial_pubkey, pubkey_for_identity(sandbox, "test3"));
+    assert_eq!(
+        "GAKSH6AD2IPJQELTHIOWDAPYX74YELUOWJLI2L4RIPIPZH6YQIFNUSDC",
+        pubkey_for_identity(sandbox, "test3").trim()
+    );
+}

cmd/soroban-cli/src/commands/keys/add.rs

@@ -31,6 +31,9 @@ pub enum Error {
 
     #[error("secret input error")]
     PasswordRead,
+
+    #[error("An identity with the name '{0}' already exists")]
+    IdentityAlreadyExists(String),
 }
 
 #[derive(Debug, clap::Parser, Clone)]
@@ -48,11 +51,24 @@ pub struct Cmd {
     /// Add a public key, ed25519, or muxed account, e.g. G1.., M2..
     #[arg(long, conflicts_with = "seed_phrase", conflicts_with = "secret_key")]
     pub public_key: Option<String>,
+
+    /// Overwrite existing identity if it already exists.
+    #[arg(long)]
+    pub overwrite: bool,
 }
 
 impl Cmd {
     pub fn run(&self, global_args: &global::Args) -> Result<(), Error> {
         let print = Print::new(global_args.quiet);
+
+        if self.config_locator.read_identity(&self.name).is_ok() {
+            if !self.overwrite {
+                return Err(Error::IdentityAlreadyExists(self.name.to_string()));
+            }
+
+            print.exclaimln(format!("Overwriting identity '{}'", &self.name.to_string()));
+        }
+
         let key = if let Some(key) = self.public_key.as_ref() {
             key.parse()?
         } else {