feat: add Atlas Cloud provider

docs/docs/models/providers/additional.md

@@ -2,8 +2,8 @@
 title: Additional Providers
 social:
   title: Additional Providers
-  tagline: Configure Groq, Aliyun, OpenRouter, TensorZero, and generic endpoints.
-  description: Configure Groq, Aliyun, OpenRouter, TensorZero, and generic endpoints.
+  tagline: Configure Atlas Cloud, Groq, Aliyun, OpenRouter, TensorZero, and generic endpoints.
+  description: Configure Atlas Cloud, Groq, Aliyun, OpenRouter, TensorZero, and generic endpoints.
   alt: fast-agent social card — Additional model providers
 ---
 
@@ -33,6 +33,7 @@ Run `fast-agent check` after adding credentials to confirm they are visible to f
 
 | Provider | Config key | API key environment variable | Default endpoint | Model string examples |
 | --- | --- | --- | --- | --- |
+| Atlas Cloud | `atlascloud` | `ATLASCLOUD_API_KEY` | `https://api.atlascloud.ai/v1` | `atlascloud.qwen/qwen3.8-max` |
 | Groq | `groq` | `GROQ_API_KEY` | `https://api.groq.com/openai/v1` | `groq.openai/gpt-oss-120b` |
 | Aliyun | `aliyun` | `ALIYUN_API_KEY` | `https://dashscope-intl.aliyuncs.com/compatible-mode/v1` | `qwen-turbo`, `aliyun.qwen3-max` |
 | OpenRouter | `openrouter` | `OPENROUTER_API_KEY` | `https://openrouter.ai/api/v1` | `openrouter.google/gemini-2.5-pro-exp-03-25:free` |
@@ -48,6 +49,21 @@ Run `fast-agent check` after adding credentials to confirm they are visible to f
 
 Use these when the provider exposes an OpenAI-compatible API but has its own credentials, model catalog, or small behavior differences.
 
+### Atlas Cloud
+
+```yaml
+atlascloud:
+  api_key: "${ATLASCLOUD_API_KEY}"
+```
+
+```bash
+fast-agent --model atlascloud.qwen/qwen3.8-max
+```
+
+Atlas Cloud uses its OpenAI-compatible Chat Completions endpoint. The provider
+defaults to `qwen/qwen3.8-max`; set `default_model` or pass an explicit model
+string to use another model from the Atlas Cloud catalog.
+
 ### Groq
 
 ```yaml

examples/setup/fast-agent.yaml

@@ -86,6 +86,12 @@ anthropic:
 #   # base_url: "https://api.moonshot.ai/v1"
 #   # default_model: "kimi-k3"
 
+# Atlas Cloud OpenAI-compatible Chat Completions provider:
+# atlascloud:
+#   api_key: "${ATLASCLOUD_API_KEY}"
+#   # base_url: "https://api.atlascloud.ai/v1"
+#   # default_model: "qwen/qwen3.8-max"
+
 #shell_execution:
 # model-facing shell tools: auto (Grok shell/Process; others Bash/Process),
 # minimal_process, grok_shell, or native

src/fast_agent/cli/commands/check_config.py

@@ -126,6 +126,10 @@ class ProviderCatalogScope:
         display_name="OpenRouter",
         providers=(Provider.OPENROUTER,),
     ),
+    "atlascloud": ProviderCatalogScope(
+        display_name="Atlas Cloud",
+        providers=(Provider.ATLASCLOUD,),
+    ),
 }
 
 _PROVIDER_CATALOG_SCOPE_ALIASES: dict[str, str] = {
@@ -147,6 +151,7 @@ class ProviderCatalogScope:
     "xai",
     "metaai",
     "openrouter",
+    "atlascloud",
     "responses",
     "codexresponses",
 )

src/fast_agent/config.py

@@ -1513,6 +1513,26 @@ class OpenRouterSettings(BaseModel):
     model_config = ConfigDict(extra="allow", arbitrary_types_allowed=True)
 
 
+class AtlasCloudSettings(BaseModel):
+    """Settings for Atlas Cloud's OpenAI-compatible API."""
+
+    api_key: str | None = Field(default=None, description="Atlas Cloud API key")
+    base_url: str | None = Field(
+        default=None,
+        description="Override API endpoint (default: https://api.atlascloud.ai/v1)",
+    )
+    default_model: str | None = Field(
+        default=None,
+        description="Default model when Atlas Cloud is selected without an explicit model",
+    )
+    default_headers: dict[str, str] | None = Field(
+        default=None,
+        description="Custom headers for all API requests",
+    )
+
+    model_config = ConfigDict(extra="allow", arbitrary_types_allowed=True)
+
+
 class AzureSettings(BaseModel):
     """Settings for using Azure OpenAI Service in the fast-agent application."""
 
@@ -2314,6 +2334,9 @@ def _migrate_legacy_mcp_settings(cls, values: Any) -> Any:
     openrouter: OpenRouterSettings | None = None
     """Settings for using OpenRouter models in the fast-agent application"""
 
+    atlascloud: AtlasCloudSettings | None = None
+    """Settings for using Atlas Cloud models in the fast-agent application"""
+
     generic: GenericSettings | None = None
     """Settings for using Generic models in the fast-agent application"""
 

src/fast_agent/llm/model_factory.py

@@ -131,6 +131,10 @@ def __call__(self, **kwargs: Any) -> FastAgentLLMProtocol: ...
         "MetaAIResponsesLLM",
     ),
     Provider.OPENROUTER: ("fast_agent.llm.provider.openai.llm_openrouter", "OpenRouterLLM"),
+    Provider.ATLASCLOUD: (
+        "fast_agent.llm.provider.openai.llm_atlascloud",
+        "AtlasCloudLLM",
+    ),
     Provider.TENSORZERO: (
         "fast_agent.llm.provider.openai.llm_tensorzero_openai",
         "TensorZeroOpenAILLM",

src/fast_agent/llm/model_selection.py

@@ -135,6 +135,14 @@ class ModelSelectionCatalog:
         Provider.ZAI: (_builtin_entry("zaiglm", display_label="GLM 5.2"),),
         Provider.MOONSHOT: (_builtin_entry("kimik3", display_label="Kimi K3"),),
         Provider.OPENROUTER: (),
+        Provider.ATLASCLOUD: (
+            CatalogModelEntry(
+                alias="qwen3.8-max",
+                model="atlascloud.qwen/qwen3.8-max",
+                display_label="Qwen3.8 Max",
+                fast=True,
+            ),
+        ),
         Provider.ALIYUN: (
             _builtin_entry("qwen-turbo", fast=True),
             _builtin_entry("qwen3-max"),

src/fast_agent/llm/provider/openai/llm_atlascloud.py

@@ -0,0 +1,24 @@
+from fast_agent.llm.provider.openai.llm_openai_compatible import OpenAICompatibleLLM
+from fast_agent.llm.provider_types import Provider
+from fast_agent.types import RequestParams
+
+ATLASCLOUD_BASE_URL = "https://api.atlascloud.ai/v1"
+DEFAULT_ATLASCLOUD_MODEL = "qwen/qwen3.8-max"
+
+
+class AtlasCloudLLM(OpenAICompatibleLLM):
+    """Atlas Cloud provider using its OpenAI-compatible Chat Completions API."""
+
+    def __init__(self, **kwargs) -> None:
+        kwargs.pop("provider", None)
+        super().__init__(provider=Provider.ATLASCLOUD, **kwargs)
+
+    def _initialize_default_params(self, kwargs: dict) -> RequestParams:
+        return self._initialize_default_params_with_model_fallback(kwargs, DEFAULT_ATLASCLOUD_MODEL)
+
+    def _provider_base_url(self) -> str:
+        base_url = None
+        if self.context.config and self.context.config.atlascloud:
+            base_url = self.context.config.atlascloud.base_url
+
+        return base_url if base_url else ATLASCLOUD_BASE_URL

src/fast_agent/llm/provider_types.py

@@ -32,6 +32,7 @@ def config_name(self) -> str:
     GOOGLE = ("google", "Google")  # For Google GenAI native library
     OPENAI = ("openai", "OpenAI")
     OPENROUTER = ("openrouter", "OpenRouter")
+    ATLASCLOUD = ("atlascloud", "Atlas Cloud")
     TENSORZERO = ("tensorzero", "TensorZero")  # For TensorZero Gateway
     AZURE = ("azure", "Azure")  # Azure OpenAI Service
     ALIYUN = ("aliyun", "Aliyun")  # Aliyun Bailian OpenAI Service

src/fast_agent/ui/model_picker_common.py

@@ -48,6 +48,7 @@
     Provider.BEDROCK,
     Provider.ALIYUN,
     Provider.OPENROUTER,
+    Provider.ATLASCLOUD,
     Provider.FAST_AGENT,
 )
 

tests/unit/fast_agent/commands/test_check_config_model_catalog.py

@@ -118,6 +118,15 @@ def test_show_provider_model_catalog_moonshot_includes_curated_model(capsys) ->
     assert "moonshot.kimi-k3" in _collapse(output)
 
 
+def test_show_provider_model_catalog_atlascloud_includes_curated_model(capsys) -> None:
+    show_provider_model_catalog("atlascloud")
+
+    output = capsys.readouterr().out
+    assert "Atlas Cloud model catalog (curated)" in output
+    assert "qwen3.8-max" in output
+    assert "atlascloud.qwen/qwen3.8-max" in _collapse(output)
+
+
 def test_show_models_overview_includes_provider_args_and_named_aliases(
     tmp_path: Path,
     capsys,

tests/unit/fast_agent/llm/providers/test_provider_default_models.py

@@ -13,6 +13,7 @@
 import os
 
 from fast_agent.config import (
+    AtlasCloudSettings,
     AzureSettings,
     DeepSeekSettings,
     HuggingFaceSettings,
@@ -25,6 +26,7 @@
 from fast_agent.context import Context
 from fast_agent.llm.model_database import ModelDatabase
 from fast_agent.llm.provider.google.llm_google_native import GoogleNativeLLM
+from fast_agent.llm.provider.openai.llm_atlascloud import AtlasCloudLLM
 from fast_agent.llm.provider.openai.llm_azure import AzureOpenAILLM
 from fast_agent.llm.provider.openai.llm_deepseek import DeepSeekResponsesLLM
 from fast_agent.llm.provider.openai.llm_generic import GenericLLM
@@ -155,6 +157,26 @@ def test_openrouter_provider_base_url_prefers_config_over_env() -> None:
             os.environ["OPENROUTER_BASE_URL"] = original_env
 
 
+def test_atlascloud_provider_uses_default_model_and_base_url() -> None:
+    llm = AtlasCloudLLM(context=Context(config=Settings()), model="")
+
+    assert llm.default_request_params.model == "qwen/qwen3.8-max"
+    assert llm._base_url() == "https://api.atlascloud.ai/v1"
+
+
+def test_atlascloud_provider_uses_config_overrides() -> None:
+    settings = Settings(
+        atlascloud=AtlasCloudSettings(
+            base_url="https://atlas-gateway.example/v1",
+            default_model="openai/gpt-oss-120b",
+        )
+    )
+    llm = AtlasCloudLLM(context=Context(config=settings), model="")
+
+    assert llm.default_request_params.model == "openai/gpt-oss-120b"
+    assert llm._base_url() == "https://atlas-gateway.example/v1"
+
+
 def test_huggingface_provider_default_model_used_with_provider_suffix() -> None:
     settings = Settings(
         hf=HuggingFaceSettings(

tests/unit/fast_agent/llm/test_model_factory.py

@@ -22,6 +22,7 @@
 from fast_agent.llm.model_selection import ModelSelectionCatalog
 from fast_agent.llm.provider.anthropic.llm_anthropic import AnthropicLLM
 from fast_agent.llm.provider.anthropic.llm_anthropic_vertex import AnthropicVertexLLM
+from fast_agent.llm.provider.openai.llm_atlascloud import AtlasCloudLLM
 from fast_agent.llm.provider.openai.llm_generic import GenericLLM
 from fast_agent.llm.provider.openai.llm_huggingface import HuggingFaceLLM
 from fast_agent.llm.provider.openai.llm_openai import OpenAILLM
@@ -87,6 +88,18 @@ def test_full_model_strings():
         assert config.reasoning_effort == exp_effort
 
 
+def test_atlascloud_model_string_and_factory() -> None:
+    config = ModelFactory.parse_model_string("atlascloud.qwen/qwen3.8-max")
+    assert config.provider == Provider.ATLASCLOUD
+    assert config.model_name == "qwen/qwen3.8-max"
+
+    factory = ModelFactory.create_factory("atlascloud.qwen/qwen3.8-max")
+    llm = factory(LlmAgent(AgentConfig(name="Atlas Cloud Test")))
+
+    assert isinstance(llm, AtlasCloudLLM)
+    assert llm.provider == Provider.ATLASCLOUD
+
+
 def test_deprecated_reasoning_suffix_is_rejected() -> None:
     with pytest.raises(ModelConfigError, match=r"Use '\?reasoning=<value>' instead"):
         ModelFactory.parse_model_string("openai.o1.high")

tests/unit/fast_agent/llm/test_model_selection_catalog.py

@@ -463,6 +463,15 @@ def test_openrouter_all_models_use_discovered_models_when_no_curated(monkeypatch
     assert models == ["openrouter.openai/gpt-4.1-mini"]
 
 
+def test_atlascloud_catalog_includes_default_model() -> None:
+    entries = ModelSelectionCatalog.list_current_entries(Provider.ATLASCLOUD)
+
+    assert len(entries) == 1
+    assert entries[0].alias == "qwen3.8-max"
+    assert entries[0].model == "atlascloud.qwen/qwen3.8-max"
+    assert entries[0].fast is True
+
+
 def test_overlay_catalog_uses_explicit_environment_context(
     monkeypatch,
     tmp_path: Path,