diff --git a/agent_fastapi.py b/agent_fastapi.py
index ae9ebab..c179b65 100644
--- a/agent_fastapi.py
+++ b/agent_fastapi.py
@@ -54,6 +54,7 @@
 )
 from open_storyline.config import load_settings, default_config_path
 from open_storyline.config import Settings
+from open_storyline.model_presets import list_model_presets, resolve_model_preset
 from open_storyline.storage.agent_memory import ArtifactStore
 from open_storyline.mcp.hooks.node_interceptors import ToolInterceptor
 from open_storyline.mcp.hooks.chat_middleware import set_mcp_log_sink, reset_mcp_log_sink
@@ -1274,7 +1275,7 @@ def __init__(self, session_id: str, cfg: Settings):
         default_llm = _peek_builtin_model_name("llm", self.cfg)
         default_vlm = _peek_builtin_model_name("vlm", self.cfg)
 
-        self.chat_models = [default_llm, CUSTOM_MODEL_KEY]
+        self.chat_models = [default_llm, *list_model_presets("llm"), CUSTOM_MODEL_KEY]
         self.chat_model_key = default_llm
 
         self.vlm_models = [default_vlm, CUSTOM_MODEL_KEY]
@@ -1934,6 +1935,14 @@ async def ensure_agent(self) -> None:
             if not isinstance(self.custom_llm_config, dict):
                 raise RuntimeError("please fill in model/base_url/api_key of custom LLM")
             llm_override = self.custom_llm_config
+        elif self.chat_model_key in list_model_presets("llm"):
+            llm_override, err = resolve_model_preset("llm", self.chat_model_key)
+            if err:
+                raise RuntimeError(err)
+            for key in ("timeout", "temperature", "max_retries", "top_p", "max_tokens"):
+                value = getattr(self.cfg.llm, key, None)
+                if value not in (None, ""):
+                    llm_override[key] = value
         else:
             llm_override, err = _resolve_builtin_model_override("llm", self.cfg.llm)
             if err:
diff --git a/src/open_storyline/model_presets.py b/src/open_storyline/model_presets.py
new file mode 100644
index 0000000..c6b6139
--- /dev/null
+++ b/src/open_storyline/model_presets.py
@@ -0,0 +1,44 @@
+from __future__ import annotations
+
+import os
+from typing import Any, Dict, Mapping, Optional, Tuple
+
+
+ATLAS_CLOUD_MODEL_KEY = "Atlas Cloud"
+
+_MODEL_PRESETS = {
+    "llm": {
+        ATLAS_CLOUD_MODEL_KEY: {
+            "model": "deepseek-ai/deepseek-v4-pro",
+            "base_url": "https://api.atlascloud.ai/v1",
+            "api_key_env": ("ATLASCLOUD_API_KEY", "ATLAS_CLOUD_API_KEY"),
+        },
+    },
+}
+
+
+def list_model_presets(kind: str) -> list[str]:
+    return list(_MODEL_PRESETS.get(kind.strip().lower(), {}))
+
+
+def resolve_model_preset(
+    kind: str,
+    key: str,
+    environ: Optional[Mapping[str, str]] = None,
+) -> Tuple[Optional[Dict[str, Any]], Optional[str]]:
+    kind = kind.strip().lower()
+    preset = _MODEL_PRESETS.get(kind, {}).get(key)
+    if preset is None:
+        return None, f"unknown {kind} model preset: {key}"
+
+    env = os.environ if environ is None else environ
+    api_key_env = preset["api_key_env"]
+    api_key = next((env.get(name, "").strip() for name in api_key_env if env.get(name, "").strip()), "")
+    if not api_key:
+        return None, f"{key} requires one of: {', '.join(api_key_env)}"
+
+    return {
+        "model": preset["model"],
+        "base_url": preset["base_url"],
+        "api_key": api_key,
+    }, None
diff --git a/tests/test_model_presets.py b/tests/test_model_presets.py
new file mode 100644
index 0000000..7141d51
--- /dev/null
+++ b/tests/test_model_presets.py
@@ -0,0 +1,51 @@
+import unittest
+
+from open_storyline.model_presets import (
+    ATLAS_CLOUD_MODEL_KEY,
+    list_model_presets,
+    resolve_model_preset,
+)
+
+
+class ModelPresetTests(unittest.TestCase):
+    def test_atlas_cloud_is_available_for_llm_only(self):
+        self.assertEqual(list_model_presets("llm"), [ATLAS_CLOUD_MODEL_KEY])
+        self.assertEqual(list_model_presets("vlm"), [])
+
+    def test_atlas_cloud_resolves_openai_compatible_config(self):
+        config, error = resolve_model_preset(
+            "llm",
+            ATLAS_CLOUD_MODEL_KEY,
+            {"ATLASCLOUD_API_KEY": "test-key"},
+        )
+
+        self.assertIsNone(error)
+        self.assertEqual(
+            config,
+            {
+                "model": "deepseek-ai/deepseek-v4-pro",
+                "base_url": "https://api.atlascloud.ai/v1",
+                "api_key": "test-key",
+            },
+        )
+
+    def test_atlas_cloud_accepts_legacy_env_name(self):
+        config, error = resolve_model_preset(
+            "llm",
+            ATLAS_CLOUD_MODEL_KEY,
+            {"ATLAS_CLOUD_API_KEY": "legacy-key"},
+        )
+
+        self.assertIsNone(error)
+        self.assertEqual(config["api_key"], "legacy-key")
+
+    def test_atlas_cloud_reports_missing_api_key(self):
+        config, error = resolve_model_preset("llm", ATLAS_CLOUD_MODEL_KEY, {})
+
+        self.assertIsNone(config)
+        self.assertIn("ATLASCLOUD_API_KEY", error)
+        self.assertIn("ATLAS_CLOUD_API_KEY", error)
+
+
+if __name__ == "__main__":
+    unittest.main()