diff --git a/crates/config/src/towerfile.rs b/crates/config/src/towerfile.rs
index aa385e1a..703c999d 100644
--- a/crates/config/src/towerfile.rs
+++ b/crates/config/src/towerfile.rs
@@ -12,6 +12,9 @@ pub struct Parameter {
 
     #[serde(default)]
     pub default: String,
+
+    #[serde(default)]
+    pub hidden: bool,
 }
 
 #[derive(Deserialize, Serialize, Debug)]
@@ -122,6 +125,7 @@ impl Towerfile {
             name,
             description,
             default,
+            hidden: false,
         });
     }
 }
@@ -272,6 +276,26 @@ mod test {
         assert_eq!(towerfile.parameters.len(), 2);
         assert_eq!(towerfile.parameters[0].name, "my_first_param");
         assert_eq!(towerfile.parameters[1].name, "my_second_param");
+        assert!(!towerfile.parameters[0].hidden);
+    }
+
+    #[test]
+    fn test_parses_secret_parameters() {
+        let toml = r#"
+            [app]
+            name = "my-app"
+            script = "./script.py"
+            source = ["*.py"]
+
+            [[parameters]]
+            name = "MY_PARAMETER"
+            hidden = true
+        "#;
+
+        let towerfile = crate::Towerfile::from_toml(toml).unwrap();
+        assert_eq!(towerfile.parameters.len(), 1);
+        assert_eq!(towerfile.parameters[0].name, "MY_PARAMETER");
+        assert!(towerfile.parameters[0].hidden);
     }
 
     #[test]
diff --git a/crates/tower-api/src/models/parameter.rs b/crates/tower-api/src/models/parameter.rs
index ce85288d..f53c7b45 100644
--- a/crates/tower-api/src/models/parameter.rs
+++ b/crates/tower-api/src/models/parameter.rs
@@ -23,6 +23,9 @@ pub struct Parameter {
     #[serde_as(as = "DefaultOnNull")]
     #[serde(rename = "name")]
     pub name: String,
+    #[serde(default)]
+    #[serde(rename = "hidden")]
+    pub hidden: bool,
 }
 
 impl Parameter {
@@ -31,6 +34,7 @@ impl Parameter {
             default,
             description,
             name,
+            hidden: false,
         }
     }
 }
diff --git a/crates/tower-api/src/models/run_parameter.rs b/crates/tower-api/src/models/run_parameter.rs
index 7e9164d4..f45cc23d 100644
--- a/crates/tower-api/src/models/run_parameter.rs
+++ b/crates/tower-api/src/models/run_parameter.rs
@@ -20,10 +20,17 @@ pub struct RunParameter {
     #[serde_as(as = "DefaultOnNull")]
     #[serde(rename = "value")]
     pub value: String,
+    #[serde(default)]
+    #[serde(rename = "hidden")]
+    pub hidden: bool,
 }
 
 impl RunParameter {
     pub fn new(name: String, value: String) -> RunParameter {
-        RunParameter { name, value }
+        RunParameter {
+            name,
+            value,
+            hidden: false,
+        }
     }
 }
diff --git a/crates/tower-cmd/src/api.rs b/crates/tower-cmd/src/api.rs
index f3ddc421..e4024606 100644
--- a/crates/tower-cmd/src/api.rs
+++ b/crates/tower-cmd/src/api.rs
@@ -840,7 +840,11 @@ pub async fn create_schedule(
     let run_parameters = parameters.map(|params| {
         params
             .into_iter()
-            .map(|(key, value)| RunParameter { name: key, value })
+            .map(|(key, value)| RunParameter {
+                name: key,
+                value,
+                hidden: false,
+            })
             .collect()
     });
 
@@ -874,7 +878,11 @@ pub async fn update_schedule(
     let run_parameters = parameters.map(|params| {
         params
             .into_iter()
-            .map(|(key, value)| RunParameter { name: key, value })
+            .map(|(key, value)| RunParameter {
+                name: key,
+                value,
+                hidden: false,
+            })
             .collect()
     });
 
diff --git a/crates/tower-cmd/src/mcp.rs b/crates/tower-cmd/src/mcp.rs
index 95d9440d..efe7e2a0 100644
--- a/crates/tower-cmd/src/mcp.rs
+++ b/crates/tower-cmd/src/mcp.rs
@@ -889,7 +889,22 @@ IMPORTANT REMINDERS:
     async fn tower_schedules_list(&self) -> Result<CallToolResult, McpError> {
         match api::list_schedules(&self.config, None, None).await {
             Ok(response) => {
-                Self::json_success(serde_json::json!({"schedules": response.schedules}))
+                let schedules = response
+                    .schedules
+                    .into_iter()
+                    .map(|mut schedule| {
+                        if let Some(parameters) = schedule.parameters.as_mut() {
+                            for parameter in parameters {
+                                if parameter.hidden {
+                                    parameter.value = "[hidden]".to_string();
+                                }
+                            }
+                        }
+                        schedule
+                    })
+                    .collect::<Vec<_>>();
+
+                Self::json_success(serde_json::json!({"schedules": schedules}))
             }
             Err(e) => Self::error_result("Failed to list schedules", e),
         }
diff --git a/crates/tower/src/lib.rs b/crates/tower/src/lib.rs
index 751f4ba6..1549e234 100644
--- a/crates/tower/src/lib.rs
+++ b/crates/tower/src/lib.rs
@@ -23,8 +23,8 @@ mod bindings {
 
         let spec = PackageSpec::from_towerfile(&towerfile);
 
-        let runtime = tokio::runtime::Runtime::new()
-            .map_err(|e| PyRuntimeError::new_err(e.to_string()))?;
+        let runtime =
+            tokio::runtime::Runtime::new().map_err(|e| PyRuntimeError::new_err(e.to_string()))?;
 
         let output = PathBuf::from(output);
 
@@ -40,8 +40,7 @@ mod bindings {
                 .as_ref()
                 .ok_or_else(|| PyRuntimeError::new_err("package build produced no output file"))?;
 
-            std::fs::copy(src, &output)
-                .map_err(|e| PyRuntimeError::new_err(e.to_string()))?;
+            std::fs::copy(src, &output).map_err(|e| PyRuntimeError::new_err(e.to_string()))?;
 
             Ok(())
         })
@@ -53,8 +52,8 @@ mod bindings {
     ///     args: Command line arguments (typically sys.argv).
     #[pyfunction]
     fn _run_cli(args: Vec<String>) -> PyResult<()> {
-        let runtime = tokio::runtime::Runtime::new()
-            .map_err(|e| PyRuntimeError::new_err(e.to_string()))?;
+        let runtime =
+            tokio::runtime::Runtime::new().map_err(|e| PyRuntimeError::new_err(e.to_string()))?;
 
         // App::new_from_args() must run inside block_on because
         // Session::from_config_dir() requires an active tokio reactor.