Boomerang Wellbeing Planner — MCP Server

A Node.js MCP (Model Context Protocol) server that generates personalised 12-week wellbeing planners for Australian near-retirees. It exposes a single MCP tool over Streamable HTTP (so it is reachable over a network URL from clients like ServiceNow), calls the Anthropic API to generate the plan content, and serves an interactive "journey path" visualisation of each plan.

What it does

1. An MCP client calls the generate_wellbeing_plan tool with a free-text wellbeing concern.
2. The server asks Claude (default model: claude-sonnet-5) for a 12-week, milestone-based plan, grounded in ABS statistics about loneliness and community participation among older Australians. The response is schema-constrained, parsed, and validated. The plan never contains medical or clinical advice — sensitive topics are framed as "worth discussing with a GP or counsellor".
3. The plan is stored (in-memory + a simple JSON file, no database) and rendered as a warm, calm HTML journey: one node per week on a connected path, colour-coded by responsible agent (wellbeing = rose, connection = blue), with a circular progress ring showing the overall wellbeing score.
4. The tool returns both the raw JSON plan and a view_url to that page.

Everything runs on one server / one port: POST /mcp (MCP endpoint) and GET /plans/:plan_id (viewer).

Setting the ANTHROPIC_API_KEY secret in Replit

1. Open the Repl and click Tools → Secrets (padlock icon).
2. Add a secret with key ANTHROPIC_API_KEY and your key from console.anthropic.com as the value.
3. Click Run. Replit installs dependencies on boot and starts the server on $PORT.

Optional secrets: ANTHROPIC_MODEL (defaults to claude-sonnet-5) and BASE_URL (auto-detected on Replit). For local development, copy .env.example to .env.

MCP tool schema

Tool: generate_wellbeing_plan

Input:

Field	Type	Required	Description
user_query	string	yes	The user's free-text wellbeing concern
emotional_state	string	no	e.g. "lonely", "anxious", "low motivation"
age_bracket	string	no	e.g. "65-70"

Output (returned as JSON text content):

{
  "plan": {
    "plan_id": "<uuid>",
    "generated_at": "<iso datetime>",
    "overall_wellbeing_score": 62,
    "weeks": [
      {
        "week_offset": 0,
        "theme": "Gentle first steps",
        "milestones": [
          {
            "title": "Take a 20-minute morning walk twice this week",
            "target_date": "Week 1",
            "owner": "retiree",
            "agent_responsible": "wellbeing",
            "confidence": 0.85
          }
        ]
      }
    ]
  },
  "view_url": "https://<repl-domain>/plans/<plan_id>"
}

weeks covers offsets 0–11, with a check-in week every 3 weeks. owner is "retiree" or "agent"; agent_responsible is "wellbeing" or "connection"; confidence is 0.00–1.00.

Testing it manually

With curl

The MCP Streamable HTTP transport takes JSON-RPC over POST. Call the tool directly:

curl -s -X POST "http://localhost:3000/mcp" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
      "name": "generate_wellbeing_plan",
      "arguments": {
        "user_query": "I retire in 6 months and I am worried I will feel lonely and aimless",
        "emotional_state": "anxious",
        "age_bracket": "65-70"
      }
    }
  }'

(Replace http://localhost:3000 with your Repl URL.) List the available tools with "method": "tools/list", "params": {}. The response includes the plan JSON and the view_url — open it in a browser to see the interactive journey.

With MCP Inspector

npx @modelcontextprotocol/inspector

Choose transport Streamable HTTP, enter https://<your-repl>/mcp, connect, and run generate_wellbeing_plan from the Tools tab.

REST endpoint: render a plan as a PNG

POST /render-plan-image takes a plan JSON (the same weeks[] schema shown above) and renders it server-side to a PNG using node-canvas — no headless browser involved.

Response: { "image_base64": "<png bytes as base64>", "content_type": "image/png" }. Returns 400 with a clear message if weeks is missing. The canvas is 900px wide with a 1400px minimum height, growing taller if the plan's milestones need the room.

curl -s -X POST "http://localhost:3000/render-plan-image" \
  -H "Content-Type: application/json" \
  -d @plan.json | node -e "
    let d=''; process.stdin.on('data',c=>d+=c).on('end',()=>{
      require('fs').writeFileSync('plan.png', Buffer.from(JSON.parse(d).image_base64,'base64'));
      console.log('wrote plan.png');
    })"

Dependency note: the canvas package is an optional dependency (its prebuilt binary installs cleanly on Replit/Linux). On platforms where it can't build, the server falls back to the API-compatible @napi-rs/canvas automatically.

Local development

npm install
cp .env.example .env   # add your ANTHROPIC_API_KEY
npm start              # http://localhost:3000

Project layout

server.js            Express app: /mcp (Streamable HTTP, stateless) + /plans/:id viewer
src/generatePlan.js  Anthropic API call, schema-constrained output, validation
src/renderPlan.js    Self-contained HTML journey-path renderer
src/planStore.js     In-memory store persisted to data/plans.json
.replit / replit.nix Replit run + environment config

Note: This project provides general lifestyle planning only — never medical or psychological advice.