feat: add Forge as LLM provider for ACE-Step-1.5

.env.example

@@ -58,6 +58,10 @@ ACESTEP_INIT_LLM=auto
 # API key for authentication (optional)
 # ACESTEP_API_KEY=sk-your-secret-key
 
+# Forge external LM settings (optional)
+# FORGE_API_KEY=your-forge-api-key
+# FORGE_API_BASE=https://api.forge.tensorblock.co/v1
+
 # ==================== Gradio UI Settings ====================
 # Server port (default: 7860)
 # PORT=7860
@@ -75,4 +79,4 @@ ACESTEP_INIT_LLM=auto
 # ==================== Startup Settings ====================
 # By default models are lazy-loaded on first request (fast server startup).
 # Set to false to force eager model loading at startup.
-# ACESTEP_NO_INIT=true
+# ACESTEP_NO_INIT=true

acestep/text_tasks/external_ai_request_helpers.py

@@ -134,7 +134,7 @@ def build_request_for_protocol(
         "max_tokens": max_tokens or int(os.getenv("ACESTEP_OPENAI_MAX_TOKENS", "3072")),
         "temperature": 0.4,
     }
-    if require_json_output and provider in {"openai", "zai"}:
+    if require_json_output and provider in {"openai", "forge", "zai"}:
         payload["response_format"] = {"type": "json_object"}
         payload["stop"] = ["```"]
     if disable_thinking and provider == "zai":

acestep/text_tasks/external_ai_request_helpers_test.py

@@ -127,6 +127,24 @@ def test_build_request_for_protocol_requests_json_output_for_openai_format(self)
         self.assertEqual(payload["stop"], ["```"])
         self.assertNotIn("thinking", payload)
 
+    def test_build_request_for_protocol_requests_json_output_for_forge_format(self) -> None:
+        """Forge format-mode requests should use OpenAI-compatible JSON output flags."""
+
+        payload, _headers = build_request_for_protocol(
+            protocol="openai_chat",
+            provider="forge",
+            api_key="test-key",
+            model="OpenAI/gpt-4o-mini",
+            messages=[{"role": "system", "content": "s"}, {"role": "user", "content": "u"}],
+            base_url="https://api.forge.tensorblock.co/v1/chat/completions",
+            max_tokens=768,
+            require_json_output=True,
+        )
+
+        self.assertEqual(payload["response_format"], {"type": "json_object"})
+        self.assertEqual(payload["stop"], ["```"])
+        self.assertNotIn("thinking", payload)
+
     def test_build_request_for_protocol_disables_zai_thinking_and_requests_json(self) -> None:
         """Z.ai format calls should disable thinking and request JSON output."""
 

acestep/text_tasks/external_lm_providers.py

@@ -53,6 +53,20 @@ class ExternalProviderProfile:
             ("OpenAI chat completions", "https://api.openai.com/v1/chat/completions"),
         ),
     ),
+    "forge": ExternalProviderProfile(
+        provider_id="forge",
+        label="Forge",
+        protocol="openai_chat",
+        default_model="OpenAI/gpt-4o-mini",
+        default_base_url="https://api.forge.tensorblock.co/v1/chat/completions",
+        api_key_env="FORGE_API_KEY",
+        api_key_required=True,
+        secret_path_env="ACESTEP_FORGE_SECRET_PATH",
+        secret_file_name="forge_api_key.enc",
+        base_url_presets=(
+            ("Forge chat completions", "https://api.forge.tensorblock.co/v1/chat/completions"),
+        ),
+    ),
     "claude": ExternalProviderProfile(
         provider_id="claude",
         label="Anthropic Claude",
@@ -101,7 +115,7 @@ def get_external_provider_profile(provider: str | None) -> ExternalProviderProfi
 def get_external_provider_choices() -> list[tuple[str, str]]:
     """Return provider dropdown choices as ``(label, value)`` pairs."""
 
-    order = ("zai", "openai", "claude", "ollama")
+    order = ("zai", "openai", "forge", "claude", "ollama")
     return [
         (_EXTERNAL_PROVIDER_PROFILES[provider_id].label, provider_id)
         for provider_id in order

acestep/text_tasks/external_lm_providers_test.py

@@ -6,21 +6,50 @@
 
 from acestep.text_tasks.external_lm_providers import (
     CUSTOM_BASE_URL_PRESET,
+    build_external_model_choice,
     get_external_base_url_preset_choices,
     get_external_base_url_preset_value,
+    get_external_provider_choices,
     get_external_provider_profile,
 )
 
 
 class ExternalLmProvidersTests(unittest.TestCase):
     """Verify provider lookup and base-URL preset helpers stay explicit."""
 
+    def test_get_external_provider_profile_returns_forge_defaults(self) -> None:
+        """Forge should use its dedicated OpenAI-compatible defaults."""
+
+        profile = get_external_provider_profile("forge")
+
+        self.assertEqual(profile.protocol, "openai_chat")
+        self.assertEqual(profile.default_model, "OpenAI/gpt-4o-mini")
+        self.assertEqual(
+            profile.default_base_url,
+            "https://api.forge.tensorblock.co/v1/chat/completions",
+        )
+        self.assertEqual(profile.api_key_env, "FORGE_API_KEY")
+
     def test_get_external_provider_profile_rejects_unknown_provider(self) -> None:
         """Unknown providers should fail fast instead of silently defaulting."""
 
         with self.assertRaises(ValueError):
             get_external_provider_profile("mystery")
 
+    def test_get_external_provider_choices_includes_forge(self) -> None:
+        """Provider choices should expose Forge to the external LM picker."""
+
+        choices = get_external_provider_choices()
+
+        self.assertIn(("Forge", "forge"), choices)
+
+    def test_build_external_model_choice_defaults_forge_model(self) -> None:
+        """Missing Forge model names should fall back to the provider default."""
+
+        choice = build_external_model_choice("forge", "")
+
+        self.assertEqual(choice, "external:forge:OpenAI/gpt-4o-mini")
+
     def test_base_url_preset_helpers_use_shared_custom_token(self) -> None:
         """Custom base-URL selection should use the centralized custom token."""