List available tools in an AgentCore gateway
To list all available tools that an AgentCore gateway provides, make a POST request to the gateway's MCP endpoint and specify tools/list as the method in the request body:
POST /mcp HTTP/1.1
Host: ${GatewayEndpoint}
Content-Type: application/json
Authorization: ${Authorization header}
${RequestBody}
Replace the following values:
-
${GatewayEndpoint} – The URL of the gateway, as provided in the response of the CreateGateway API.
-
${Authorization header} – The authorization credentials from the identity provider when you set up inbound authorization.
-
${RequestBody} – The JSON payload of the request body, as specified in Listing tools in the Model Context Protocol (MCP). Include tools/list as the method.
The response returns a list of available tools with their names, descriptions, and parameter schemas.
Code samples for listing tools
To see examples of listing available tools in the gateway, select one of the following methods:
- Python requests package
-
import requests
import json
def list_tools(gateway_url, access_token):
headers = {
"Content-Type": "application/json",
"Authorization": f"Bearer {access_token}"
}
payload = {
"jsonrpc": "2.0",
"id": "list-tools-request",
"method": "tools/list"
}
response = requests.post(gateway_url, headers=headers, json=payload)
return response.json()
# Example usage
gateway_url = "https://${GatewayEndpoint}/mcp" # Replace with your actual gateway endpoint
access_token = "${AccessToken}" # Replace with your actual access token
tools = list_tools(gateway_url, access_token)
print(json.dumps(tools, indent=2))
- MCP Client
-
import asyncio
from mcp import ClientSession
from mcp.client.streamable_http import streamablehttp_client
async def execute_mcp(
url,
token,
headers=None
):
default_headers = {
"Authorization": f"Bearer {token}"
}
headers = {**default_headers, **(headers or {})}
async with streamablehttp_client(
url=url,
headers=headers,
) as (
read_stream,
write_stream,
callA,
):
async with ClientSession(read_stream, write_stream) as session:
# 1. Perform initialization handshake
print("Initializing MCP...")
_init_response = await session.initialize()
print(f"MCP Server Initialize successful! - {_init_response}")
# 2. List available tools
print("Listing tools...")
cursor = True
tools = []
while cursor:
next_cursor = cursor
if type(cursor) == bool:
next_cursor = None
list_tools_response = await session.list_tools(next_cursor)
tools.extend(list_tools_response.tools)
cursor = list_tools_response.nextCursor
tool_names = []
if tools:
for tool in tools:
tool_names.append(tool.name)
tool_names_string = "\n".join(tool_names)
print(
f"List MCP tools. # of tools - {len(tools)}"
f"List of tools - \n{tool_names_string}\n"
)
async def main():
url = "https://${GatewayEndpoint}/mcp"
token = "your_bearer_token_here"
# Optional additional headers
additional_headers = {
"Content-Type": "application/json",
}
await execute_mcp(
url=url,
token=token,
headers=additional_headers
)
# Run the async function
if __name__ == "__main__":
asyncio.run(main())
- Strands MCP Client
-
from strands.tools.mcp.mcp_client import MCPClient
from mcp.client.streamable_http import streamablehttp_client
import os
def create_streamable_http_transport(mcp_url: str, access_token: str):
return streamablehttp_client(mcp_url, headers={"Authorization": f"Bearer {access_token}"})
def get_full_tools_list(client):
"""
List tools w/ support for pagination
"""
more_tools = True
tools = []
pagination_token = None
while more_tools:
tmp_tools = client.list_tools_sync(pagination_token=pagination_token)
tools.extend(tmp_tools)
if tmp_tools.pagination_token is None:
more_tools = False
else:
more_tools = True
pagination_token = tmp_tools.pagination_token
return tools
def run_agent(mcp_url: str, access_token: str):
mcp_client = MCPClient(lambda: create_streamable_http_transport(mcp_url, access_token))
with mcp_client:
tools = get_full_tools_list(mcp_client)
print(f"Found the following tools: {[tool.tool_name for tool in tools]}")
run_agent(<MCP URL>, <Access token>)
- LangGraph MCP Client
-
import asyncio
from langchain_mcp_adapters.client import MultiServerMCPClient
def list_tools(
url,
headers
):
mcp_client = MultiServerMCPClient(
{
"agent": {
"transport": "streamable_http",
"url": url,
"headers": headers,
}
}
)
tools = asyncio.run(mcp_client.get_tools())
tool_details = []
tool_names = []
for tool in tools:
tool_names.append(f"{tool.name}")
tool_detail = f"{tool.name} - {tool.description} \n"
tool_properties = tool.args_schema.get('properties', {})
properties = []
for property_name, tool_property in tool_properties.items():
properties.append(f"{property_name} - {tool_property.get('description', None)} \n")
tool_details.append(f"{tool_detail}{"\n".join(properties)}")
tool_details_string = "\n".join(tool_details)
tool_names_string = "\n".join(tool_names)
print(
f"Langchain: List MCP tools. # of tools - {len(tools)}\n",
f"Langchain: List of tool names - \n{tool_names_string}\n"
f"Langchain: Details of tools - \n{tool_details_string}\n"
)
If search is enabled on the gateway, then the search tool, x_amz_bedrock_agentcore_search
will be listed first in the response.