SEP-1686: Tasks (#1645)

examples/clients/simple-task-client/mcp_simple_task_client/__main__.py

@@ -0,0 +1,5 @@
+import sys
+
+from .main import main
+
+sys.exit(main())  # type: ignore[call-arg]

examples/clients/simple-task-client/mcp_simple_task_client/main.py

@@ -0,0 +1,55 @@
+"""Simple task client demonstrating MCP tasks polling over streamable HTTP."""
+
+import asyncio
+
+import click
+from mcp import ClientSession
+from mcp.client.streamable_http import streamablehttp_client
+from mcp.types import CallToolResult, TextContent
+
+
+async def run(url: str) -> None:
+    async with streamablehttp_client(url) as (read, write, _):
+        async with ClientSession(read, write) as session:
+            await session.initialize()
+
+            # List tools
+            tools = await session.list_tools()
+            print(f"Available tools: {[t.name for t in tools.tools]}")
+
+            # Call the tool as a task
+            print("\nCalling tool as a task...")
+
+            result = await session.experimental.call_tool_as_task(
+                "long_running_task",
+                arguments={},
+                ttl=60000,
+            )
+            task_id = result.task.taskId
+            print(f"Task created: {task_id}")
+
+            # Poll until done (respects server's pollInterval hint)
+            async for status in session.experimental.poll_task(task_id):
+                print(f"  Status: {status.status} - {status.statusMessage or ''}")
+
+            # Check final status
+            if status.status != "completed":
+                print(f"Task ended with status: {status.status}")
+                return
+
+            # Get the result
+            task_result = await session.experimental.get_task_result(task_id, CallToolResult)
+            content = task_result.content[0]
+            if isinstance(content, TextContent):
+                print(f"\nResult: {content.text}")
+
+
+@click.command()
+@click.option("--url", default="http://localhost:8000/mcp", help="Server URL")
+def main(url: str) -> int:
+    asyncio.run(run(url))
+    return 0
+
+
+if __name__ == "__main__":
+    main()