2 files changed, 73 insertions, 0 deletions
diff --git a/internal/appconfig/config_alias_test.go b/internal/appconfig/config_alias_test.go
new file mode 100644
index 0000000..6cc5bda
--- /dev/null
+++ b/internal/appconfig/config_alias_test.go
@@ -0,0 +1,36 @@
+package appconfig
+
+import (
+    "log"
+    "os"
+    "path/filepath"
+    "testing"
+)
+
+func TestOpenAIPresets_AliasResolution(t *testing.T) {
+    dir := t.TempDir()
+    t.Setenv("XDG_CONFIG_HOME", dir)
+    cfgDir := filepath.Join(dir, "hexai")
+    if err := os.MkdirAll(cfgDir, 0o755); err != nil {
+        t.Fatalf("mkdir: %v", err)
+    }
+    toml := `
+[provider]
+name = "openai"
+
+[openai]
+model = "codex"
+
+[openai.presets]
+codex = "gpt-5-codex"
+`
+    path := filepath.Join(cfgDir, "config.toml")
+    if err := os.WriteFile(path, []byte(toml), 0o644); err != nil {
+        t.Fatalf("write: %v", err)
+    }
+    cfg := Load(log.New(os.Stderr, "test ", 0))
+    if cfg.OpenAIModel != "gpt-5-codex" {
+        t.Fatalf("expected alias to resolve to gpt-5-codex, got %q", cfg.OpenAIModel)
+    }
+}
+
diff --git a/internal/appconfig/config_env_model_test.go b/internal/appconfig/config_env_model_test.go
new file mode 100644
index 0000000..2db2bb5
--- /dev/null
+++ b/internal/appconfig/config_env_model_test.go
@@ -0,0 +1,37 @@
+package appconfig
+
+import (
+    "log"
+    "os"
+    "testing"
+)
+
+// Test that HEXAI_MODEL applies to provider model fields and that
+// provider-specific envs take precedence when both are set.
+func TestEnv_GenericModelOverrideAndPrecedence(t *testing.T) {
+    t.Setenv("HEXAI_MODEL", "gpt-5-codex")
+    t.Setenv("HEXAI_PROVIDER", "openai")
+    // No provider-specific env set yet: HEXAI_MODEL should flow into OpenAIModel
+    cfg := Load(log.New(os.Stderr, "test ", 0))
+    if cfg.OpenAIModel != "gpt-5-codex" {
+        t.Fatalf("expected OpenAIModel=gpt-5-codex via HEXAI_MODEL, got %q", cfg.OpenAIModel)
+    }
+
+    // Now set a provider-specific model; it should win over HEXAI_MODEL
+    t.Setenv("HEXAI_OPENAI_MODEL", "gpt-5-thinking")
+    cfg2 := Load(log.New(os.Stderr, "test ", 0))
+    if cfg2.OpenAIModel != "gpt-5-thinking" {
+        t.Fatalf("expected OpenAIModel from HEXAI_OPENAI_MODEL to win, got %q", cfg2.OpenAIModel)
+    }
+}
+
+// Test that HEXAI_MODEL_FORCE overrides provider-specific envs (used by CLI --model).
+func TestEnv_ModelForce_OverridesProviderSpecific(t *testing.T) {
+    t.Setenv("HEXAI_OPENAI_MODEL", "gpt-5-main")
+    t.Setenv("HEXAI_MODEL_FORCE", "gpt-5-codex")
+    t.Setenv("HEXAI_PROVIDER", "openai")
+    cfg := Load(log.New(os.Stderr, "test ", 0))
+    if cfg.OpenAIModel != "gpt-5-codex" {
+        t.Fatalf("expected OpenAIModel forced to gpt-5-codex, got %q", cfg.OpenAIModel)
+    }
+}