Phase 3b: FastMCP "ai service" for claude.ai cooking mode

A standalone MCP server (no Django import) exposing 7 tools over
Streamable HTTP, backed by the Django REST API via the caine token.

- mcp_server/: client.py (httpx wrapper over /api/), server.py (the
  tools + FastMCP app + main), __main__.py, tests.py.
- Tools: get_pantry, set_item_state, add_to_pantry, what_can_i_cook,
  get_recipes, log_cook (suggests, never mutates), create_meta_recipe
  (brainstorm -> commit). Each description says when to call it.
- deploy/food-mcp.service: systemd unit (own process, runs .venv python
  -m mcp_server, loads /var/lib/food/.env).
- deploy/food.tomflux.xyz.nginx: current config + an authless
  /mcp/<secret>/ location proxying to 127.0.0.1:8765 (the URL secret is
  the credential; SSE-friendly buffering/timeout).
- pyproject: [dependency-groups] mcp = [fastmcp, httpx]; deploy with
  `uv sync --group mcp`.

Verified: 7 tools register on fastmcp 3.x, run() accepts transport/
host/port/path, 6 FoodClient unit tests pass (httpx MockTransport).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

1 files changed, 71 insertions, 0 deletions

diff --git a/deploy/food.tomflux.xyz.nginx b/deploy/food.tomflux.xyz.nginx
new file mode 100644
index 0000000..0d4a357
--- /dev/null
+++ b/deploy/food.tomflux.xyz.nginx
@@ -0,0 +1,71 @@
+# nginx config for food.tomflux.xyz
+# Adds the MCP location to the existing web-app server block.
+#
+# The MCP connector is "authless" from claude.ai's side — the long secret in the
+# URL path IS the credential. Only that exact prefix is proxied to the FastMCP
+# service; everything else under /mcp/ falls through to the catch-all 301.
+# Generate the secret once and keep it out of git, e.g.:
+#     python -c "import secrets; print(secrets.token_urlsafe(32))"
+# then replace REPLACE_WITH_LONG_SECRET below and in the claude.ai connector URL:
+#     https://food.tomflux.xyz/mcp/REPLACE_WITH_LONG_SECRET/
+
+server {
+    server_name food.tomflux.xyz;
+
+    location /app/ {
+        proxy_pass http://127.0.0.1:8042;
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto $scheme;
+    }
+
+    location /accounts/ {
+        proxy_pass http://127.0.0.1:8042;
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto $scheme;
+    }
+
+    location /static/ {
+        proxy_pass http://127.0.0.1:8042;
+    }
+
+    # --- MCP server (claude.ai cooking-mode connector) ---
+    # Trailing slashes on both sides strip the secret prefix, so the FastMCP
+    # service (serving at "/") sees clean paths.
+    location /mcp/REPLACE_WITH_LONG_SECRET/ {
+        proxy_pass http://127.0.0.1:8765/;
+        proxy_http_version 1.1;
+        proxy_set_header Host $host;
+        proxy_set_header X-Forwarded-Proto $scheme;
+        proxy_buffering off;            # MCP Streamable HTTP / SSE
+        proxy_read_timeout 3600s;
+    }
+
+    location / {
+        return 301 /app/;
+    }
+
+    # Block API and admin from external access (MCP reaches the API over
+    # localhost, so this does not affect it).
+    location /api/ { return 404; }
+    location /admin/ { return 404; }
+
+    listen 443 ssl; # managed by Certbot
+    ssl_certificate /etc/letsencrypt/live/dav.jihakuz.xyz/fullchain.pem; # managed by Certbot
+    ssl_certificate_key /etc/letsencrypt/live/dav.jihakuz.xyz/privkey.pem; # managed by Certbot
+    include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
+    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot
+}
+
+server {
+    if ($host = food.tomflux.xyz) {
+        return 301 https://$host$request_uri;
+    } # managed by Certbot
+
+    server_name food.tomflux.xyz;
+    listen 80;
+    return 404; # managed by Certbot
+}