weather-mcp-server

An MCP server wrapping the Open-Meteo API, deployed on GCP Cloud Run. No API key required — Open-Meteo is free and open.

Tools

Tool	Description
get_current_weather	Current conditions for a lat/lon
get_forecast	Up to 16-day daily (or hourly) forecast
get_historical_weather	Historical daily data for a date range

Local development

# Install dependencies
pip install -r requirements.txt

# Run the server
uvicorn app.main:app --reload --port 8080

# Health check
curl http://localhost:8080/health

# Test with MCP Inspector
npx @modelcontextprotocol/inspector http://localhost:8080/mcp

GCP Setup (one-time)

1. Enable APIs

gcloud services enable run.googleapis.com artifactregistry.googleapis.com \
  --project=weather-mcp-project

2. Create Artifact Registry repository

gcloud artifacts repositories create mcp-images \
  --repository-format=docker \
  --location=us-central1 \
  --description="Docker images for weather-mcp-server" \
  --project=weather-mcp-project

3. Set cleanup policy (keeps storage within free 0.5 GB tier)

gcloud artifacts repositories set-cleanup-policies mcp-images \
  --project=weather-mcp-project \
  --location=us-central1 \
  --policy='[{"name":"keep-last-2","action":{"type":"Keep"},"mostRecentVersions":{"keepCount":2}}]'

4. Create a Service Account for GitHub Actions

gcloud iam service-accounts create github-actions-sa \
  --display-name="GitHub Actions SA" \
  --project=weather-mcp-project

# Grant required roles
for role in roles/run.admin roles/artifactregistry.writer roles/iam.serviceAccountUser; do
  gcloud projects add-iam-policy-binding weather-mcp-project \
    --member="serviceAccount:github-actions-sa@weather-mcp-project.iam.gserviceaccount.com" \
    --role="$role"
done

# Export key
gcloud iam service-accounts keys create sa-key.json \
  --iam-account=github-actions-sa@weather-mcp-project.iam.gserviceaccount.com

5. Add GitHub repository secrets

In your repo → Settings → Secrets and variables → Actions, add:

Secret	Value
GCP_SA_KEY	Contents of sa-key.json (delete the file after!)

The project ID and region are hardcoded in the workflow — no secret needed for those.

Deployment

Push to main — GitHub Actions builds the Docker image, pushes it to Artifact Registry, and deploys to Cloud Run automatically.

Smoke test (post-deploy)

CLOUD_RUN_URL=https://<your-cloud-run-url>

# Health
curl $CLOUD_RUN_URL/health

# List MCP tools
curl -X POST $CLOUD_RUN_URL/mcp \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"tools/list","id":1}'

Cost

Everything runs within GCP free tier limits at typical personal/dev usage. See PLAN.md for the full breakdown.