feat: add Atlas Cloud Chat Completions support

.env.example

@@ -48,10 +48,13 @@ POE_API_KEY=your-poe-api-key-here
 #QWEN API KEY
 QWEN_API_KEY=your-qwen-key-here
 
+# Atlas Cloud API Key
+ATLASCLOUD_API_KEY=your-atlascloud-key-here
+
 # Exa API Key (for Exa AI-powered web search MCP server)
 EXA_API_KEY=your-exa-api-key-here
 
 #Azure OpenAI Configuration
 AZURE_OPENAI_API_KEY=your-azure-openai-key-here
 AZURE_OPENAI_ENDPOINT=your-azure-openai-endpoint-here
-AZURE_OPENAI_API_VERSION=your-azure-openai-api-version-here
+AZURE_OPENAI_API_VERSION=your-azure-openai-api-version-here

docs/source/reference/supported_models.rst

@@ -156,7 +156,7 @@ The ``chatcompletion`` backend provides a generic way to connect to any OpenAI-c
    * - **Backend Type**
      - ``chatcompletion``
    * - **Compatible Providers**
-     - Cerebras AI, Together AI, Fireworks AI, Groq, OpenRouter, POE, and any OpenAI-compatible API
+     - Cerebras AI, Together AI, Fireworks AI, Groq, OpenRouter, Atlas Cloud, POE, and any OpenAI-compatible API
    * - **Required Config**
      - ``base_url`` pointing to the provider's API endpoint
    * - **API Key**
@@ -216,13 +216,17 @@ The ``chatcompletion`` backend provides a generic way to connect to any OpenAI-c
    * - **POE**
      - Platform-specific
      - Platform credentials
+   * - **Atlas Cloud**
+     - ``https://api.atlascloud.ai/v1``
+     - ``ATLASCLOUD_API_KEY``
 
 **Common Models:**
 
 * **Cerebras**: ``gpt-oss-120b``, ``gpt-oss-70b``
 * **Together AI**: ``meta-llama/Meta-Llama-3.1-405B-Instruct-Turbo``, ``mistralai/Mixtral-8x7B-Instruct-v0.1``
 * **Fireworks AI**: ``accounts/fireworks/models/llama-v3p1-405b-instruct``
 * **Groq**: ``llama-3.1-70b-versatile``, ``mixtral-8x7b-32768``
+* **Atlas Cloud**: use a model ID available to your Atlas Cloud account
 
 Tool Enablement Reference
 --------------------------

massgen/backend/chat_completions.py

@@ -15,6 +15,7 @@
 - ZAI: ZAI_API_KEY
 - POE: POE_API_KEY
 - Qwen: QWEN_API_KEY
+- Atlas Cloud: ATLASCLOUD_API_KEY
 """
 
 from __future__ import annotations
@@ -1145,6 +1146,8 @@ def get_provider_name(self) -> str:
             return "POE"
         elif "aliyuncs.com" in base_url:
             return "Qwen"
+        elif "atlascloud.ai" in base_url:
+            return "Atlas Cloud"
         else:
             return "ChatCompletion"
 

massgen/cli/backends.py

@@ -92,6 +92,7 @@ def create_backend(backend_type: str, **kwargs) -> Any:
     - Nvidia NIM (nvidia.com) -> NGC_API_KEY
     - POE (poe.com) -> POE_API_KEY
     - Qwen (dashscope.aliyuncs.com) -> QWEN_API_KEY
+    - Atlas Cloud (atlascloud.ai) -> ATLASCLOUD_API_KEY
 
     External agent frameworks are supported via the adapter registry.
     """
@@ -238,6 +239,15 @@ def create_backend(backend_type: str, **kwargs) -> Any:
                     raise ConfigurationError(
                         "Qwen API key not found. Set QWEN_API_KEY environment variable.\n" "You can add it to a .env file in:\n" "  - Current directory: .env\n" "  - Global config: ~/.massgen/.env",
                     )
+            elif base_url and "atlascloud.ai" in base_url:
+                api_key = os.getenv("ATLASCLOUD_API_KEY")
+                if not api_key:
+                    raise ConfigurationError(
+                        "Atlas Cloud API key not found. Set ATLASCLOUD_API_KEY environment variable.\n"
+                        "You can add it to a .env file in:\n"
+                        "  - Current directory: .env\n"
+                        "  - Global config: ~/.massgen/.env",
+                    )
 
         return ChatCompletionsBackend(api_key=api_key, **kwargs)
 

massgen/configs/BACKEND_CONFIGURATION.md

@@ -328,7 +328,7 @@ backend:
 
 Generic backend supporting multiple providers (v0.0.18+ with MCP).
 
-Supports: Cerebras AI, Together AI, Fireworks AI, Groq, Nebius AI Studio, OpenRouter, Kimi/Moonshot, and any OpenAI-compatible API.
+Supports: Cerebras AI, Together AI, Fireworks AI, Groq, Nebius AI Studio, OpenRouter, Kimi/Moonshot, Atlas Cloud, and any OpenAI-compatible API.
 
 ```yaml
 backend:
@@ -365,6 +365,7 @@ backend:
 - **OpenRouter**: `https://openrouter.ai/api/v1`
 - **Nvidia NIM**: `https://integrate.api.nvidia.com/v1`
 - **Kimi/Moonshot**: `https://api.moonshot.cn/v1`
+- **Atlas Cloud**: `https://api.atlascloud.ai/v1`
 
 ---
 
@@ -464,4 +465,4 @@ NOTION_API_KEY=your-notion-key
 
 - [Join our Discord](https://discord.massgen.ai)
 - [Report Issues](https://github.com/Leezekun/MassGen/issues)
-- [View Documentation](https://github.com/Leezekun/MassGen)
+- [View Documentation](https://github.com/Leezekun/MassGen)

massgen/configs/basic/single/single_atlascloud.yaml

@@ -0,0 +1,12 @@
+# MassGen Atlas Cloud Configuration
+# uv run massgen --automation --config massgen/configs/basic/single/single_atlascloud.yaml "Hello"
+agents:
+  - id: "atlascloud_agent"
+    backend:
+      type: "chatcompletion"
+      model: "qwen/qwen3.8-max"
+      base_url: "https://api.atlascloud.ai/v1"
+
+ui:
+  display_type: "textual_terminal"
+  logging_enabled: true

massgen/tests/test_chat_completions_refactor.py

@@ -15,6 +15,8 @@
     BACKGROUND_TOOL_STATUS_NAME,
     BACKGROUND_TOOL_WAIT_NAME,
 )
+from massgen.cli.backends import create_backend
+from massgen.cli.config_loading import ConfigurationError
 
 
 def test_openai_backend_defaults():
@@ -47,6 +49,41 @@ def test_cerebras_backend():
     assert backend.config["base_url"] == "https://api.cerebras.ai/v1"
 
 
+def test_atlascloud_backend():
+    """Provider should be inferred from the Atlas Cloud base URL."""
+    backend = ChatCompletionsBackend(
+        base_url="https://api.atlascloud.ai/v1",
+        api_key="test-key",
+    )
+    assert backend.get_provider_name() == "Atlas Cloud"
+    assert backend.config["base_url"] == "https://api.atlascloud.ai/v1"
+
+
+def test_atlascloud_api_key_is_detected(monkeypatch: pytest.MonkeyPatch):
+    """Atlas Cloud configs should use ATLASCLOUD_API_KEY automatically."""
+    monkeypatch.setenv("ATLASCLOUD_API_KEY", "test-atlas-key")
+
+    backend = create_backend(
+        "chatcompletion",
+        base_url="https://api.atlascloud.ai/v1",
+        model="qwen/qwen3.8-max",
+    )
+
+    assert backend.api_key == "test-atlas-key"
+
+
+def test_atlascloud_api_key_error_is_actionable(monkeypatch: pytest.MonkeyPatch):
+    """Missing Atlas Cloud credentials should name the expected variable."""
+    monkeypatch.delenv("ATLASCLOUD_API_KEY", raising=False)
+
+    with pytest.raises(ConfigurationError, match="ATLASCLOUD_API_KEY"):
+        create_backend(
+            "chatcompletion",
+            base_url="https://api.atlascloud.ai/v1",
+            model="qwen/qwen3.8-max",
+        )
+
+
 @pytest.mark.asyncio
 async def test_tool_conversion_via_api_params_handler():
     """Response-style function tools are converted via ChatCompletionsAPIParamsHandler."""