mcp-server/src/legal_mcp/server.py

@@ -6,6 +6,7 @@ Run with: python -m legal_mcp.server
 from __future__ import annotations
 
 import logging
+import os
 import sys
 from collections.abc import AsyncIterator
 from contextlib import asynccontextmanager
@@ -41,11 +42,28 @@ async def lifespan(server: FastMCP) -> AsyncIterator[None]:
         logger.info("Ezer Mishpati MCP server stopped")
 
 
+# HTTP listener address, used only when MCP_TRANSPORT selects an HTTP transport.
+#
+# These MUST be passed to the constructor rather than left to FastMCP's own
+# FASTMCP_HOST / FASTMCP_PORT environment settings: FastMCP.__init__ declares
+# `host: str = "127.0.0.1"` and `port: int = 8000` as explicit keyword defaults
+# and forwards them into Settings(**settings). In pydantic-settings, explicit
+# init kwargs outrank environment variables — so FASTMCP_PORT is silently
+# ignored and the server binds 8000 regardless (verified 2026-08-05; on this
+# host 8000 is already taken, so it failed loudly by luck rather than design).
+#
+# Default to loopback: this transport is unauthenticated until #231.2 lands and
+# the registry contains destructive tools.
+MCP_HTTP_HOST = os.environ.get("MCP_HTTP_HOST", "127.0.0.1")
+MCP_HTTP_PORT = int(os.environ.get("MCP_HTTP_PORT", "8790"))
+
 # Create MCP server
 mcp = FastMCP(
     "Ezer Mishpati - עוזר משפטי",
     instructions="מערכת AI לסיוע בניסוח החלטות משפטיות בסגנון דפנה תמיר",
     lifespan=lifespan,
+    host=MCP_HTTP_HOST,
+    port=MCP_HTTP_PORT,
 )
 
 # ── Import and register tools ───────────────────────────────────────
@@ -1260,7 +1278,44 @@ async def corroboration_rebuild(case_law_id: str = "") -> dict:
 
 
 def main():
-    mcp.run(transport="stdio")
+    """Run the server on the transport named by ``MCP_TRANSPORT`` (default stdio).
+
+    ONE server, two transports — deliberately not a second implementation (G2).
+    The tool registry, services and DB pool above are shared verbatim; only the
+    wire protocol differs, so a tool can never exist on one transport and not
+    the other.
+
+    - ``stdio`` (default) — the historical path. Every interactive Claude Code
+      session reaches us this way via the ``legal-ai`` entry in ``~/.claude.json``.
+      Changing this default would break them all, so it stays the default.
+    - ``streamable-http`` — required by the agent-platform port. Agents driven
+      over the Agent Client Protocol receive their MCP servers from the *client*
+      at session start, and that channel accepts HTTP servers only: each is
+      injected as ``{type:"http", name, url, headers:[Bearer]}``. A stdio server
+      has no path into such a session at all, which is why platform-driven agents
+      lost all 108 tools when their execution engine changed — TaskMaster #231.
+      Platform-side wiring lives behind the port (``web/agent_platform_port.py``),
+      not here; this module only has to be reachable over HTTP.
+
+    Host/port come from FastMCP's own ``FASTMCP_HOST`` / ``FASTMCP_PORT`` settings.
+    Bind to loopback only: this transport carries no authentication yet, and the
+    registry includes destructive tools (``case_delete``, ``precedent_library_delete``).
+    The Bearer gate is #231.2 and MUST land before this is reachable off-host.
+    """
+    transport = os.environ.get("MCP_TRANSPORT", "stdio").strip() or "stdio"
+    valid = ("stdio", "sse", "streamable-http")
+    if transport not in valid:
+        # Fail loudly — a typo must not silently fall back to stdio and leave
+        # the HTTP listener absent while everything "looks" fine (§6).
+        raise SystemExit(
+            f"MCP_TRANSPORT={transport!r} is not one of {valid}",
+        )
+    if transport != "stdio":
+        logger.info(
+            "Serving MCP over %s on %s:%s",
+            transport, mcp.settings.host, mcp.settings.port,
+        )
+    mcp.run(transport=transport)
 
 
 if __name__ == "__main__":