Strands Agent MCP

Instructions

Implementation Reference

• src/strands_agent_mcp/server.py:41-46 (handler)

  The handler function for the 'list_agents' tool. It returns a list of names of all registered agents by iterating over agent_registry.agent_entries. The @mcp.tool decorator registers it with FastMCP and provides the tool description/schema.

  @mcp.tool(description="list all available agents")
  def list_agents() -> List[str]:
      """
      List all registered agents
      """
      return [agent.name for agent in agent_registry.agent_entries]

• src/strands_agent_mcp/registry.py:33-35 (helper)

  Helper property on the Registry class that provides the list of all AgentEntry instances, which list_agents uses to extract agent names.

  @property
  def agent_entries(self) -> List[AgentEntry]:
      return [entry for entry in self._registry.values()]

• src/strands_agent_mcp/registry.py:42-47 (helper)

  Builds the agent registry by discovering agents from plugins, populating the agent_entries used by list_agents.

  def build_registry(discovered_plugins: Dict[str, ModuleType]) -> Registry:
      registry = Registry()
      for plugin_name, module in discovered_plugins.items():
          for agent_entry in module.build_agents():
              registry.register(agent_entry)
      return registry