wehub-resource-sync
49b9bb6724
Deploy Docs / deploy-docs (push) Failing after 1s
Conformance Tests / client-conformance (push) Failing after 3s
Conformance Tests / server-conformance (push) Failing after 1s
GitHub Actions Security Analysis / zizmor (push) Failing after 1s
CI / checks (push) Failing after 59m20s
CI / all-green (push) Waiting to run
71 lines
2.1 KiB
Python
71 lines
2.1 KiB
Python
from collections.abc import Sequence
|
|
from typing import Any, Literal
|
|
|
|
import mcp_types as types
|
|
|
|
from mcp import Client
|
|
from mcp.client import ClaimContext, ClientExtension, ResultClaim
|
|
from mcp.server.context import CallNext, HandlerResult, ServerRequestContext
|
|
from mcp.server.extension import Extension
|
|
from mcp.server.mcpserver import MCPServer, require_client_extension
|
|
|
|
EXTENSION_ID = "com.example/receipts"
|
|
|
|
|
|
class ReceiptResult(types.Result):
|
|
"""The claimed result shape; `result_type` pins the wire tag."""
|
|
|
|
result_type: Literal["receipt"] = "receipt"
|
|
receipt_token: str
|
|
|
|
|
|
class ReceiptIssuer(Extension):
|
|
"""Server half: answers `buy` with a receipt instead of a final result."""
|
|
|
|
identifier = EXTENSION_ID
|
|
|
|
async def intercept_tool_call(
|
|
self,
|
|
params: types.CallToolRequestParams,
|
|
ctx: ServerRequestContext[Any, Any],
|
|
call_next: CallNext,
|
|
) -> HandlerResult:
|
|
if params.name != "buy":
|
|
return await call_next(ctx)
|
|
require_client_extension(ctx, EXTENSION_ID)
|
|
return {"resultType": "receipt", "receiptToken": "r-117"}
|
|
|
|
|
|
class Receipts(ClientExtension):
|
|
"""Client half: claims the `receipt` shape and supplies the code that finishes it."""
|
|
|
|
identifier = EXTENSION_ID
|
|
|
|
def claims(self) -> Sequence[ResultClaim[Any]]:
|
|
return [ResultClaim(result_type="receipt", model=ReceiptResult, resolve=self._redeem)]
|
|
|
|
async def _redeem(self, claimed: ReceiptResult, ctx: ClaimContext) -> types.CallToolResult:
|
|
return await ctx.session.call_tool("redeem", {"token": claimed.receipt_token})
|
|
|
|
|
|
mcp = MCPServer("shop", extensions=[ReceiptIssuer()])
|
|
|
|
|
|
@mcp.tool()
|
|
def buy(item: str) -> types.CallToolResult:
|
|
"""Buy an item."""
|
|
raise NotImplementedError # ReceiptIssuer answers `buy` before the tool runs
|
|
|
|
|
|
@mcp.tool()
|
|
def redeem(token: str) -> str:
|
|
"""Exchange a receipt token for the goods."""
|
|
return f"goods for {token}"
|
|
|
|
|
|
async def main() -> None:
|
|
async with Client(mcp, extensions=[Receipts()]) as client:
|
|
result = await client.call_tool("buy", {"item": "lamp"})
|
|
print(result.content)
|
|
# [TextContent(text='goods for r-117')]
|