diff --git a/src/cortex-cli/src/acp_cmd.rs b/src/cortex-cli/src/acp_cmd.rs
index ff6a586c..951d2cf8 100644
--- a/src/cortex-cli/src/acp_cmd.rs
+++ b/src/cortex-cli/src/acp_cmd.rs
@@ -3,6 +3,7 @@
 //! The ACP protocol enables IDE integration (like Zed) with Cortex.
 //! Supports both stdio and HTTP transports for flexible integration.
 
+use crate::utils::paths::get_cortex_home;
 use anyhow::{Result, bail};
 use clap::Parser;
 use cortex_common::resolve_model_alias;
@@ -58,9 +59,7 @@ impl AcpCli {
     pub async fn run(self) -> Result<()> {
         // Validate agent exists early if specified (Issue #1958)
         if let Some(ref agent_name) = self.agent {
-            let cortex_home = dirs::home_dir()
-                .map(|h| h.join(".cortex"))
-                .ok_or_else(|| anyhow::anyhow!("Could not determine home directory"))?;
+            let cortex_home = acp_agent_registry_home();
             let cwd = std::env::current_dir().ok();
             let registry = cortex_engine::AgentRegistry::new(&cortex_home, cwd.as_deref());
             // Scan for agents in standard locations
@@ -125,6 +124,10 @@ impl AcpCli {
     }
 }
 
+fn acp_agent_registry_home() -> PathBuf {
+    get_cortex_home()
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/src/cortex-cli/tests/acp_cortex_home.rs b/src/cortex-cli/tests/acp_cortex_home.rs
new file mode 100644
index 00000000..1ebaf6f3
--- /dev/null
+++ b/src/cortex-cli/tests/acp_cortex_home.rs
@@ -0,0 +1,42 @@
+use std::process::Command;
+
+use tempfile::tempdir;
+
+#[test]
+fn acp_agent_lookup_uses_cortex_home() {
+    let temp_dir = tempdir().unwrap();
+    let agent_dir = temp_dir.path().join("agents").join("testacpagent");
+    std::fs::create_dir_all(&agent_dir).unwrap();
+    std::fs::write(
+        agent_dir.join("AGENT.md"),
+        r#"---
+name: testacpagent
+description: Test ACP agent
+---
+
+Test prompt
+"#,
+    )
+    .unwrap();
+
+    let output = Command::new(env!("CARGO_BIN_EXE_Cortex"))
+        .args([
+            "acp",
+            "--agent",
+            "testacpagent",
+            "--port",
+            "1",
+            "--host",
+            "not a socket address",
+        ])
+        .env("CORTEX_HOME", temp_dir.path())
+        .output()
+        .unwrap();
+
+    let stderr = String::from_utf8_lossy(&output.stderr);
+    assert!(!output.status.success());
+    assert!(
+        !stderr.contains("Agent not found"),
+        "ACP ignored CORTEX_HOME and failed agent lookup: {stderr}"
+    );
+}