perl-mcp

Create an MCP::Server instance with a name and version, then register tools using $server->tool() with a name, description, JSON Schema input_schema, and a code handler. The handler receives ($self, $args) and returns results via $self->text_result().

Pass a standard JSON Schema hashref as input_schema to $server->tool(), defining type, properties with per-parameter descriptions, and a required array. Clear parameter descriptions help the LLM call the tool correctly.

Yes, wrap the server in Net::Async::MCP and pass it to Langertha::Engine::Anthropic via the mcp_servers parameter. You can then use chat_with_tools_f for one-shot calls or Langertha::Raider for multi-turn agent loops.

Common causes are using the wrong handler signature or return method. The handler receives $self as an MCP::Tool instance, not your server class, and must return via $self->text_result(), passing 1 as the second argument to flag errors.

Call $self->text_result($error_message, 1) where the second argument sets is_error. Wrap risky operations in eval and check $@ to convert exceptions into proper MCP error responses.