/base-mcp

Moonwell Plugin

[!IMPORTANT] Complete the short Base MCP onboarding flow defined in SKILL.md before calling any Moonwell endpoint. The user's wallet address — required for prepare and position queries — is fetched lazily when needed.

Overview

Moonwell is a Compound v2 lending protocol on Base and Optimism. The plugin reads positions/rates and prepares unsigned calldata over the Moonwell HTTP API, then executes via send_calls. No additional MCP server required — everything goes through an HTTP call + send_calls.

Supported chains: Base (8453), Optimism (10).

Surface Routing

Moonwell is HTTP-only; every capability follows the standard HTTP routing in ../references/custom-plugins.md.

Endpoints

Read endpoints (use web_request GET)

GET https://api.moonwell.fi/v1/markets?chain=base
GET https://api.moonwell.fi/v1/markets/USDC?chain=base
GET https://api.moonwell.fi/v1/rates?chain=base&asset=USDC
GET https://api.moonwell.fi/v1/yield?chain=base&sort=apy&min-tvl=1000000&limit=5
GET https://api.moonwell.fi/v1/positions/<address>?chain=base
GET https://api.moonwell.fi/v1/health/<address>?chain=base
GET https://api.moonwell.fi/v1/rewards/<address>?chain=base
GET https://api.moonwell.fi/v1/token-balance/<address>?chain=base&asset=USDC

Market reads are edge-cached 30 s. User-scoped reads (positions, health, rewards, token-balance) are never cached.

/positions returns an array — one entry per market. Use ?active=true to filter out markets where both suppliedUsd and borrowedUsd are zero.

Prepare endpoints (use web_request → send_calls)

Verbs: supply, withdraw, borrow, repay.

GET form (query params):

GET https://api.moonwell.fi/v1/prepare/supply?chain=base&asset=USDC&amountDecimal=100&from=<address>

POST form (JSON body — pass as the body object parameter to web_request):

{
  "url": "https://api.moonwell.fi/v1/prepare/supply",
  "method": "POST",
  "headers": { "content-type": "application/json" },
  "body": { "chain": "base", "asset": "USDC", "amountDecimal": "100", "from": "<address>" }
}

Both return identical response shapes. Use GET when simpler; use POST when the body is complex.

Key parameters

Orchestration

web_request(https://api.moonwell.fi/v1/prepare/<verb>?...)
  → { data: { transactions: [ { to, data, value, chainId }, ... ] } }
      ↓
send_calls(chain, calls mapped from transactions[])
  → approvalUrl + requestId
      ↓
User approves at the returned approval URL (present as "Approve Transaction" — see ../references/approval-mode.md)
      ↓
get_request_status(requestId) → confirmed

Steps in transactions[] are ordered — approve and enter-market come before the protocol action. Execute them as a single send_calls batch.

Submission

Target tool: send_calls.

A prepare/<verb> response returns ordered transaction steps:

{
  "data": {
    "transactions": [
      { "step": "approve",          "to": "0x...", "data": "0x...", "value": "0x0", "chainId": 8453 },
      { "step": "enter-market",     "to": "0x...", "data": "0x...", "value": "0x0", "chainId": 8453 },
      { "step": "moonwell-supply",  "to": "0x...", "data": "0x...", "value": "0x0", "chainId": 8453 }
    ]
  }
}

Pass all items as the calls array to send_calls, mapping chainId from any transaction item to the Base MCP chain string (base for Base mainnet, optimism for Optimism). Then walk the approval flow (see ../references/approval-mode.md) and poll get_request_status.

Example Prompts

Supply 100 USDC on Base

1. get_wallets → address
2. web_request GET /token-balance/<address>?chain=base&asset=USDC  → confirm balance ≥ 100
3. web_request GET /prepare/supply?chain=base&asset=USDC&amountDecimal=100&from=<address>
4. send_calls(chain="base", calls from transactions[])
5. User approves → get_request_status(requestId)

Borrow USDC against collateral

1. get_wallets → address
2. web_request GET /health/<address>?chain=base    → verify health > 1.5
3. web_request GET /prepare/borrow?chain=base&asset=USDC&amountDecimal=50&from=<address>
4. send_calls(chain="base", calls from transactions[])
5. User approves → get_request_status(requestId)

Check positions and health

1. get_wallets → address
2. web_request GET /positions/<address>?chain=base&active=true  → show per-market balances
3. web_request GET /health/<address>?chain=base                 → show health factor

Risks & Warnings

• Liquidation risk. Borrowing against collateral can be liquidated if the position's health factor falls too low. Always read /health/<address> before and after a borrow or withdraw, and surface the value to the user.

Health factor guide

Notes

• mTokens — ERC-20 receipt tokens (mUSDC, mWETH…); exchange rate accrues over time
• WETH special-case — borrow/withdraw deliver native ETH; supply/repay require ERC-20 WETH. Both asset=ETH and asset=WETH resolve to the same mWETH market
• Compound v2 error codes — mint, borrow, repay return non-zero codes for business-logic failures without reverting. Check the onchain receipt after broadcast
• Base has two mUSDC entries — the current market and a deprecated bridged-USDC market. Disambiguate by marketAddress or deprecated: true

Chain IDs from Moonwell