Build MCP Server: NEAR Portfolio Tracker for Claude

Description

## Overview
Create an MCP server that lets Claude track and analyze NEAR portfolio performance - token holdings, DeFi positions, and historical returns.

## Why This Matters
Users want to understand their NEAR portfolio without manually checking multiple sites. Claude with portfolio access can provide instant insights and recommendations.

## Technical Requirements

### MCP Tools to Implement
1. **get_portfolio_summary** - Overall portfolio value and allocation
2. **get_token_holdings** - All token balances with current values
3. **get_defi_positions** - LP positions, staking, lending
4. **get_portfolio_history** - Value over time with charts
5. **calculate_pnl** - Profit/loss analysis

### Data Sources
- NEAR RPC for balances
- Ref Finance for DeFi positions
- Price feeds for valuations
- Historical data for trends

## Deliverables
1. Working MCP server with 5+ tools
2. Published to npm
3. Listed in MCP Registry
4. Documentation with examples

## Success Criteria
- Accurate portfolio tracking
- Real-time updates
- Historical analysis capability