get_polyhaven_categories

Instructions

Get a list of categories for a specific asset type on Polyhaven.

Parameters:
- asset_type: The type of asset to get categories for (hdris, textures, models, all)

Implementation Reference

• src/server.py:467-499 (handler)

  The handler function for 'get_polyhaven_categories' tool. It checks if PolyHaven is enabled, sends a command to Blender to retrieve categories for the given asset_type, formats the response by sorting categories by asset count, and returns a formatted string list. The @mcp.tool() decorator handles registration.

  @mcp.tool()
  def get_polyhaven_categories(ctx: Context, asset_type: str = "hdris") -> str:
      """
      Get a list of categories for a specific asset type on Polyhaven.
  
      Parameters:
      - asset_type: The type of asset to get categories for (hdris, textures, models, all)
      """
      try:
          blender = get_blender_connection()
          if not _polyhaven_enabled:
              return "PolyHaven integration is disabled. Select it in the sidebar in BlenderMCP, then run it again."
          result = blender.send_command(
              "get_polyhaven_categories", {"asset_type": asset_type}
          )
  
          if "error" in result:
              return f"Error: {result['error']}"
  
          # Format the categories in a more readable way
          categories = result["categories"]
          formatted_output = f"Categories for {asset_type}:\n\n"
  
          # Sort categories by count (descending)
          sorted_categories = sorted(categories.items(), key=lambda x: x[1], reverse=True)
  
          for category, count in sorted_categories:
              formatted_output += f"- {category}: {count} assets\n"
  
          return formatted_output
      except Exception as e:
          logger.error(f"Error getting Polyhaven categories: {str(e)}")
          return f"Error getting Polyhaven categories: {str(e)}"

• src/server.py:467-467 (registration)

  The @mcp.tool() decorator registers the get_polyhaven_categories function as an MCP tool.

  @mcp.tool()

• src/server.py:468-473 (schema)

  Input schema defined by function parameters: asset_type (str, default 'hdris'). Output: str (formatted categories list). Documented in docstring.

  def get_polyhaven_categories(ctx: Context, asset_type: str = "hdris") -> str:
      """
      Get a list of categories for a specific asset type on Polyhaven.
  
      Parameters:
      - asset_type: The type of asset to get categories for (hdris, textures, models, all)

• src/server.py:247-283 (helper)

  Helper function used by the tool to get Blender connection and update _polyhaven_enabled status, which is checked in the handler.

  def get_blender_connection():
      """Get or create a persistent Blender connection"""
      global _blender_connection, _polyhaven_enabled, _tripo_apikey  # Add _polyhaven_enabled to globals
  
      # If we have an existing connection, check if it's still valid
      if _blender_connection is not None:
          try:
              # First check if PolyHaven is enabled by sending a ping command
              result = _blender_connection.send_command("get_tripo_apikey")
              _tripo_apikey = result.get("api_key", "")
              result = _blender_connection.send_command("get_polyhaven_status")
              # Store the PolyHaven status globally
              _polyhaven_enabled = result.get("enabled", False)
  
              return _blender_connection
          except Exception as e:
              # Connection is dead, close it and create a new one
              logger.warning(f"Existing connection is no longer valid: {str(e)}")
              try:
                  _blender_connection.disconnect()
              except:
                  pass
              _blender_connection = None
  
      # Create a new connection if needed
      if _blender_connection is None:
          _blender_connection = BlenderConnection(host="localhost", port=9876)
          if not _blender_connection.connect():
              logger.error("Failed to connect to Blender")
              _blender_connection = None
              raise Exception(
                  "Could not connect to Blender. Make sure the Blender addon is running."
              )
          logger.info("Created new persistent connection to Blender")
  
      return _blender_connection