feat: serve stamp tools over Streamable HTTP

/mcp on 127.0.0.1:8000 when VERAE_MCP_TRANSPORT=streamable-http.

README.md

@@ -21,6 +21,12 @@ Inspector (stdio, memory ledger):
 uv run mcp dev src/verae_mcp_timestamping_server/server.py
 ```
 
+Streamable HTTP (`http://127.0.0.1:8000/mcp`):
+
+```sh
+VERAE_MCP_TRANSPORT=streamable-http uv run verae-mcp-timestamping-server
+```
+
 Tests:
 
 ```sh

src/verae_mcp_timestamping_server/server.py

@@ -63,13 +63,13 @@ async def hash_report(
 
 
 def main() -> None:
-    url = os.environ.get("VERAE_NATS_URL")
-    if url:
-        raise SystemExit(
-            "NATS leaf mode is wired through NatsLedger; "
-            "stdio Task 1 uses MemoryLedger. Set VERAE_NATS_URL on Streamable HTTP later."
-        )
     build_mcp(MemoryLedger())
+    transport = os.environ.get("VERAE_MCP_TRANSPORT", "stdio")
+    if transport == "streamable-http":
+        host = os.environ.get("VERAE_MCP_HOST", "127.0.0.1")
+        port = int(os.environ.get("VERAE_MCP_PORT", "8000"))
+        mcp.run(transport="streamable-http", host=host, port=port)
+        return
     mcp.run()
 
 

tests/test_http.py

@@ -0,0 +1,42 @@
+"""Streamable HTTP: stamp over /mcp."""
+
+import socket
+
+import anyio
+import pytest
+import uvicorn
+from mcp import Client
+
+from verae_mcp_timestamping_server.ledger import SHA256_EMPTY, MemoryLedger
+from verae_mcp_timestamping_server.server import build_mcp
+
+pytestmark = pytest.mark.anyio
+
+
+def _free_port() -> int:
+    sock = socket.socket()
+    sock.bind(("127.0.0.1", 0))
+    port = sock.getsockname()[1]
+    sock.close()
+    return port
+
+
+async def test_stamp_over_streamable_http():
+    mcp = build_mcp(MemoryLedger())
+    app = mcp.streamable_http_app()
+    port = _free_port()
+    server = uvicorn.Server(
+        uvicorn.Config(app, host="127.0.0.1", port=port, log_level="error")
+    )
+    async with anyio.create_task_group() as tg:
+        tg.start_soon(server.serve)
+        with anyio.fail_after(10):
+            while not server.started:
+                await anyio.sleep(0.05)
+        async with Client(f"http://127.0.0.1:{port}/mcp") as client:
+            result = await client.call_tool(
+                "stamp", {"sha256": SHA256_EMPTY, "scope": "local"}
+            )
+            assert result.is_error is not True
+            assert result.structured_content["receipts"][0]["hash"] == SHA256_EMPTY
+        server.should_exit = True