feat: Google Calendar MCP

Author: vorburger

docs/concepts/mcp.md

@@ -54,7 +54,7 @@ Enola will replace values of `${secret:XYZ}` with the [secret](../use/secret/ind
     TODO
 
     Zapier
-    Google Mail & Calendar & Drive!
+    Google Mail & Drive!
     RAG with Pinecone, LlamaIndex?
     OpenAPI (HF)?
 -->
@@ -93,6 +93,28 @@ The [`search-brave`](https://github.com/brave/brave-search-mcp-server) tool uses
 enola ai --agents=test/agents/brave.agent.yaml --prompt="Use the brave_news_search tool to obtain what's new in world politics today and summarize the top 7 developments in bullet points of maximum 3 sentences each."
 ```
 
+### Google Calendar
+
+Follow https://github.com/nspady/google-calendar-mcp#quick-start to obtain the GCP OAuth Key JSON file.
+
+Edit `test/mcp/google-calendar.yaml` and set `GOOGLE_OAUTH_CREDENTIALS` to the path to this JSON file. Now run:
+
+```shell
+./enola -vvvv mcp list-tools --mcp=test/mcp/google-calendar.yaml
+```
+
+This will open a web-browser, where you need to authorize access to your Google account.
+The token from this authorization will be saved to `~/.config/google-calendar-mcp/tokens.json`.
+Re-run `mcp list-tools` and make sure that it prints the calendar MCP tools.
+If that's successful, then you can use it e.g. like this:
+
+```shell
+./enola -vvvv ai --mcp=test/mcp/google-calendar.yaml --agents=test/agents/google-calendar.agent.yaml --prompt="What upcoming meetings do I have scheduled?"
+```
+
+TODO Patch `nspady/google-calendar-mcp` so that JSON can be provided via env. var. directly, not just via file?!
+Then fix https://github.com/enola-dev/enola/issues/1862 and move `test/mcp/google-calendar.yaml` to `models/enola.dev/ai/mcp.yaml`.
+
 ### Git
 
 ```yaml

test/mcp/google-calendar.yaml

@@ -0,0 +1,26 @@
+# SPDX-License-Identifier: Apache-2.0
+#
+# Copyright 2025 The Enola <https://enola.dev> Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# TODO Actually generate (!write) and publish a JSON Schema for McpServerConnectionConfig
+$schema: https://enola.dev/ai/mcp/server/connections
+
+servers:
+  google-calendar:
+    command: npx
+    args: ["-y", "@cocal/google-calendar-mcp"]
+    docs: https://github.com/nspady/google-calendar-mcp
+    env:
+      GOOGLE_OAUTH_CREDENTIALS: /home/vorburger/cal.json