select_option

Instructions

Implementation Reference

• argus/mcp_server.py:363-381 (handler)

  MCP tool handler for 'select_option'. Decorated with @mcp.tool(). Validates element index, appends step to session, calls browser.select_option(), and returns success/failure message.

  @mcp.tool()
  async def select_option(element_index: int, value: str) -> str:
      """Select an option from a dropdown/select element.
  
      Args:
          element_index: The [N] index of the select element
          value: The value or visible text to select
      """
      s = _require_session()
      if element_index < 0 or element_index >= len(s._last_elements):
          return f"Error: element index {element_index} out of range"
  
      step = f'Select "{value}" in element [{element_index}]'
      s.steps.append(step)
  
      ok = await s.browser.select_option(element_index, value, s._last_elements)
      if ok:
          return f'Selected "{value}"'
      return "Failed to select option"

• argus/browser.py:349-358 (handler)

  Low-level browser implementation of select_option. Builds a Playwright selector from the element and calls _page.select_option() with a 5-second timeout. Returns bool.

  async def select_option(
      self, element_index: int, value: str, elements: List[InteractiveElement]
  ) -> bool:
      el = elements[element_index]
      selector = self._build_selector(el)
      try:
          await self._page.select_option(selector, value, timeout=5_000)
          return True
      except Exception:
          return False

• argus/mcp_server.py:363-364 (registration)

  Registration via @mcp.tool() decorator. The function name 'select_option' becomes the tool name exposed to the MCP client (Claude Code).

  @mcp.tool()
  async def select_option(element_index: int, value: str) -> str:

• argus/mcp_server.py:249-258 (helper)

  The get_page_state() tool's docstring mentions select_option as one of the interaction methods users can use with element indices.

  @mcp.tool()
  async def get_page_state() -> str:
      """Get the current page URL, title, and all interactive elements.
  
      Returns a numbered list of elements you can interact with using
      click(index), type_text(index, text), or select_option(index, value).
      """
      s = _require_session()
      state = await s.browser.get_state()
      s._last_elements = state.elements

• argus/explorer.py:230-238 (helper)

  Explorer._execute_action handles ActionType.SELECT by calling browser.select_option() with the action's element_index and value.

  elif t == ActionType.SELECT:
      if (
          action.element_index is not None
          and action.value
          and action.element_index < len(state.elements)
      ):
          return await self.browser.select_option(
              action.element_index, action.value, state.elements
          )