lambda_function.py

import json
import tools  # noqa: F401 — registers tool handlers
from registry import auto_register, get_handler

auto_register(tools)

_DELIMITER = "___"


def lambda_handler(event, context):
    if context.client_context is None or not getattr(context.client_context, "custom", None):
        raise ValueError(
            "Missing client context. This Lambda must be invoked via AgentCore Gateway "
            "or with --client-context set (see make invoke)."
        )

    custom = context.client_context.custom
    raw_tool_name = custom["bedrockAgentCoreToolName"]
    tool_name = raw_tool_name[raw_tool_name.index(_DELIMITER) + len(_DELIMITER):]

    print(f"Invoking tool: {tool_name!r}")
    print(f"Input: {json.dumps(event)}")

    handler = get_handler(tool_name)
    result = handler(**event)

    print(f"Result: {json.dumps(result)}")
    return result