feat: add environment variable injection for Docker sandbox

- Add environment field to sandbox config for injecting env vars into container
- Support $VAR syntax to resolve values from host environment variables
- Refactor frontend API modules to use centralized getBackendBaseURL()
- Improve Doraemon skill with explicit input/output path arguments
- Add .env.example file

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.env.example

@@ -0,0 +1,11 @@
+# TAVILY API Key
+TAVILY_API_KEY=your-tavily-api-key
+
+# Jina API Key
+JINA_API_KEY=your-jina-api-key
+
+# Optional:
+# VOLCENGINE_API_KEY=your-volcengine-api-key
+# OPENAI_API_KEY=your-openai-api-key
+# GEMINI_API_KEY=your-gemini-api-key
+# DEEPSEEK_API_KEY=your-deepseek-api-key

backend/src/community/aio_sandbox/aio_sandbox_provider.py

@@ -43,6 +43,9 @@ class AioSandboxProvider(SandboxProvider):
           - host_path: /path/on/host
             container_path: /path/in/container
             read_only: false
+        environment:  # Environment variables to inject (values starting with $ are resolved from host env)
+          NODE_ENV: production
+          API_KEY: $MY_API_KEY
     """
 
     def __init__(self):
@@ -94,8 +97,29 @@ class AioSandboxProvider(SandboxProvider):
             "auto_start": sandbox_config.auto_start if sandbox_config.auto_start is not None else True,
             "container_prefix": sandbox_config.container_prefix or DEFAULT_CONTAINER_PREFIX,
             "mounts": sandbox_config.mounts or [],
+            "environment": self._resolve_env_vars(sandbox_config.environment or {}),
         }
 
+    def _resolve_env_vars(self, env_config: dict[str, str]) -> dict[str, str]:
+        """Resolve environment variable references in configuration.
+
+        Values starting with $ are resolved from host environment variables.
+
+        Args:
+            env_config: Dictionary of environment variable names to values.
+
+        Returns:
+            Dictionary with resolved environment variable values.
+        """
+        resolved = {}
+        for key, value in env_config.items():
+            if isinstance(value, str) and value.startswith("$"):
+                env_name = value[1:]  # Remove $ prefix
+                resolved[key] = os.environ.get(env_name, "")
+            else:
+                resolved[key] = str(value)
+        return resolved
+
     def _is_sandbox_ready(self, base_url: str, timeout: int = 30) -> bool:
         """Check if sandbox is ready to accept connections.
 
@@ -191,6 +215,10 @@ class AioSandboxProvider(SandboxProvider):
             container_name,
         ]
 
+        # Add configured environment variables
+        for key, value in self._config["environment"].items():
+            cmd.extend(["-e", f"{key}={value}"])
+
         # Add configured volume mounts
         for mount in self._config["mounts"]:
             host_path = mount.host_path

backend/src/config/sandbox_config.py

@@ -22,6 +22,7 @@ class SandboxConfig(BaseModel):
         auto_start: Whether to automatically start Docker container (default: true)
         container_prefix: Prefix for container names (default: deer-flow-sandbox)
         mounts: List of volume mounts to share directories with the container
+        environment: Environment variables to inject into the container (values starting with $ are resolved from host env)
     """
 
     use: str = Field(
@@ -52,5 +53,10 @@ class SandboxConfig(BaseModel):
         default_factory=list,
         description="List of volume mounts to share directories between host and container",
     )
+    environment: dict[str, str] = Field(
+        default_factory=dict,
+        description="Environment variables to inject into the sandbox container. "
+        "Values starting with $ will be resolved from host environment variables.",
+    )
 
     model_config = ConfigDict(extra="allow")

config.example.yaml

@@ -147,6 +147,14 @@ sandbox:
 #   #   - host_path: /path/on/host
 #   #     container_path: /home/user/shared
 #   #     read_only: false
+#
+#   # Optional: Environment variables to inject into the sandbox container
+#   # Values starting with $ will be resolved from host environment variables
+#   # environment:
+#   #   NODE_ENV: production
+#   #   DEBUG: "false"
+#   #   API_KEY: $MY_API_KEY        # Reads from host's MY_API_KEY env var
+#   #   DATABASE_URL: $DATABASE_URL  # Reads from host's DATABASE_URL env var
 
 # ============================================================================
 # Skills Configuration

frontend/src/core/mcp/api.ts

@@ -1,17 +1,14 @@
-import { env } from "@/env";
+import { getBackendBaseURL } from "@/core/config";
 
 import type { MCPConfig } from "./types";
 
 export async function loadMCPConfig() {
-  const response = await fetch(
-    `${env.NEXT_PUBLIC_BACKEND_BASE_URL}/api/mcp/config`,
-  );
+  const response = await fetch(`${getBackendBaseURL()}/api/mcp/config`);
   return response.json() as Promise<MCPConfig>;
 }
 
 export async function updateMCPConfig(config: MCPConfig) {
-  const response = await fetch(
-    `${env.NEXT_PUBLIC_BACKEND_BASE_URL}/api/mcp/config`,
+  const response = await fetch(`${getBackendBaseURL()}/api/mcp/config`,
     {
       method: "PUT",
       headers: {

frontend/src/core/skills/api.ts

@@ -1,16 +1,16 @@
-import { env } from "@/env";
+import { getBackendBaseURL } from "@/core/config";
 
 import type { Skill } from "./type";
 
 export async function loadSkills() {
-  const skills = await fetch(`${env.NEXT_PUBLIC_BACKEND_BASE_URL}/api/skills`);
+  const skills = await fetch(`${getBackendBaseURL()}/api/skills`);
   const json = await skills.json();
   return json.skills as Skill[];
 }
 
 export async function enableSkill(skillName: string, enabled: boolean) {
   const response = await fetch(
-    `${env.NEXT_PUBLIC_BACKEND_BASE_URL}/api/skills/${skillName}`,
+    `${getBackendBaseURL()}/api/skills/${skillName}`,
     {
       method: "PUT",
       headers: {

skills/public/doraemon-comic-aigc/SKILL.md

@@ -12,7 +12,7 @@ Generate JSON spec for 8 panels arranged on ONE 9:16 vertical canvas (1080x1920)
 1. Extract story context (theme, gadget, conflict, punchline)
 2. Map to 8 narrative beats
 3. Output JSON to `/mnt/user-data/outputs/prompt.json`
-4. Run `python /mnt/skills/custom/doraemon-comic-aigc/scripts/generate.py`
+4. Run `python /mnt/skills/custom/doraemon-comic-aigc/scripts/generate.py --input_path /mnt/user-data/outputs/prompt.json --output_path /mnt/user-data/outputs/doraemon.png `
 5. Directly present the output image as well as the `prompt.json` using the `present_files` tool without checking the file existence
 
 ## Panel Layout

skills/public/doraemon-comic-aigc/scripts/generate.py

@@ -1,10 +1,11 @@
+import argparse
 import base64
 import os
 
 import requests
 
 
-def generate_image(prompt: str) -> str:
+def generate_image(prompt: str, output_path: str) -> str:
     api_key = os.getenv("GEMINI_API_KEY")
     if not api_key:
         return "GEMINI_API_KEY is not set"
@@ -24,22 +25,25 @@ def generate_image(prompt: str) -> str:
     if len(image_parts) == 1:
         base64_image = image_parts[0]["inlineData"]["data"]
         # Save the image to a file
-        with open("/mnt/user-data/outputs/doraemon.png", "wb") as f:
+        with open(output_path, "wb") as f:
             f.write(base64.b64decode(base64_image))
-        return "Successfully generated image to /mnt/user-data/outputs/doraemon.png"
+        return f"Successfully generated image to {output_path}"
     else:
         return "Failed to generate image"
 
 
-def main():
+def main(input_path: str, output_path: str):
     with open(
-        "/mnt/user-data/outputs/prompt.json",
+        input_path,
         "r",
     ) as f:
         raw = f.read()
-        print(generate_image(raw))
+        print(generate_image(raw, output_path))
 
 
 if __name__ == "__main__":
-    main()
-    main()
+    parser = argparse.ArgumentParser(description="Generate Doraemon comic image")
+    parser.add_argument("--input_path", required=True, help="Path to the input prompt JSON file")
+    parser.add_argument("--output_path", required=True, help="Path to save the output image")
+    args = parser.parse_args()
+    main(args.input_path, args.output_path)