fix: resolve model aliases before syntax validation

rust/crates/rusty-claude-cli/Cargo.toml

@@ -23,6 +23,8 @@ serde_json.workspace = true
 syntect = "5"
 tokio = { version = "1", features = ["rt-multi-thread", "signal", "time"] }
 tools = { path = "../tools" }
+log = "0.4"
+
 
 [lints]
 workspace = true

rust/crates/rusty-claude-cli/src/main.rs

@@ -23,6 +23,8 @@ use std::sync::{Arc, Mutex};
 use std::thread::{self, JoinHandle};
 use std::time::{Duration, Instant, UNIX_EPOCH};
 
+use log::debug;
+
 use api::{
     detect_provider_kind, model_family_identity_for, resolve_startup_auth_source, AnthropicClient,
     AuthSource, ContentBlockDelta, InputContentBlock, InputMessage, MessageRequest,
@@ -718,15 +720,19 @@ fn parse_args(args: &[String]) -> Result<CliAction, String> {
                 let value = args
                     .get(index + 1)
                     .ok_or_else(|| "missing value for --model".to_string())?;
-                validate_model_syntax(value)?;
-                model = resolve_model_alias_with_config(value);
+                let resolved = resolve_model_alias_with_config(value);
+                debug!("Resolved --model '{}' -> '{}'", value, resolved);
+                validate_model_syntax(&resolved)?;
+                model = resolved;
                 model_flag_raw = Some(value.clone()); // #148
                 index += 2;
             }
             flag if flag.starts_with("--model=") => {
                 let value = &flag[8..];
-                validate_model_syntax(value)?;
-                model = resolve_model_alias_with_config(value);
+                let resolved = resolve_model_alias_with_config(value);
+                debug!("Resolved --model='{}' -> '{}'", value, resolved);
+                validate_model_syntax(&resolved)?;
+                model = resolved;
                 model_flag_raw = Some(value.to_string()); // #148
                 index += 1;
             }
@@ -15055,3 +15061,46 @@ mod dump_manifests_tests {
         let _ = fs::remove_dir_all(&root);
     }
 }
+
+#[cfg(test)]
+mod alias_resolution_tests {
+    use super::{resolve_model_alias_with_config, validate_model_syntax};
+
+    #[test]
+    fn test_alias_resolution_builtin() {
+        // Built-in aliases should resolve to their full IDs
+        assert_eq!(resolve_model_alias_with_config("opus"), "claude-opus-4-6");
+        assert_eq!(resolve_model_alias_with_config("sonnet"), "claude-sonnet-4-6");
+        assert_eq!(resolve_model_alias_with_config("haiku"), "claude-haiku-4-5-20251213");
+    }
+
+    #[test]
+    fn test_alias_resolution_syntax_validation() {
+        // Resolved aliases should pass syntax validation
+        let resolved = resolve_model_alias_with_config("opus");
+        assert!(validate_model_syntax(&resolved).is_ok());
+
+        // Raw aliases should FAIL syntax validation (this is why we resolve first!)
+        assert!(validate_model_syntax("opus").is_err());
+    }
+
+    #[test]
+    fn test_unknown_alias_fails_validation() {
+        // Unknown aliases resolve to themselves
+        let resolved = resolve_model_alias_with_config("unknown-alias");
+        assert_eq!(resolved, "unknown-alias");
+
+        // And then fail validation with a helpful error
+        let result = validate_model_syntax(&resolved);
+        assert!(result.is_err());
+        assert!(result.unwrap_err().contains("invalid model syntax"));
+    }
+
+    #[test]
+    fn test_direct_provider_model_passes() {
+        // Direct provider/model strings should remain unchanged and pass
+        let model = "openai/gpt-4o";
+        assert_eq!(resolve_model_alias_with_config(model), model);
+        assert!(validate_model_syntax(model).is_ok());
+    }
+}

rust/crates/rusty-claude-cli/tests/mock_parity_harness.rs

@@ -1,7 +1,7 @@
 use std::collections::BTreeMap;
 use std::fs;
 use std::io::Write;
-use std::os::unix::fs::PermissionsExt;
+
 use std::path::{Path, PathBuf};
 use std::process::{Command, Output, Stdio};
 use std::sync::atomic::{AtomicU64, Ordering};
@@ -426,11 +426,15 @@ fn prepare_plugin_fixture(workspace: &HarnessWorkspace) {
         "#!/bin/sh\nINPUT=$(cat)\nprintf '{\"plugin\":\"%s\",\"tool\":\"%s\",\"input\":%s}\\n' \"$CLAWD_PLUGIN_ID\" \"$CLAWD_TOOL_NAME\" \"$INPUT\"\n",
     )
     .expect("plugin script should write");
-    let mut permissions = fs::metadata(&script_path)
-        .expect("plugin script metadata")
-        .permissions();
-    permissions.set_mode(0o755);
-    fs::set_permissions(&script_path, permissions).expect("plugin script should be executable");
+    #[cfg(unix)]
+    {
+        use std::os::unix::fs::PermissionsExt;
+        let mut permissions = fs::metadata(&script_path)
+            .expect("plugin script metadata")
+            .permissions();
+        permissions.set_mode(0o755);
+        fs::set_permissions(&script_path, permissions).expect("plugin script should be executable");
+    }
 
     fs::write(
         manifest_dir.join("plugin.json"),