# formatUnits

A read tool on the MCP Ethers Wallet MCP server.

Agent View of the PolicyLayer registry record for `formatUnits`. HTML page: https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/formatunits

## Facts

- Tool: `formatUnits`
- Server: MCP Ethers Wallet (`crazyrabbitltc/mcp-ethers-server`) — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server.md
- Homepage: https://github.com/crazyrabbitLTC/mcp-ethers-server
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Allowed

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "formatUnits",
    "arguments": {}
  }
}
```

## Why formatUnits is rated Low

formatUnits is a standard ethers.js utility that converts blockchain values to human-readable format. It performs no state changes, does not execute transactions, and has no destructive or financial implications. The low severity reflects that misuse would only produce incorrect output formatting, not data loss or unauthorized transactions.

From the tool's own definition: "Tool name 'formatUnits' suggests a utility function for formatting numerical values (likely converting wei to readable Ether units). The empty description provides no evidence of side effects, data modification, or financial operations."

## Use case

AI agents call formatUnits to retrieve information from MCP Ethers Wallet without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches MCP Ethers Wallet:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "formatUnits": {}
  }
}
```

## Other tools on MCP Ethers Wallet (68)

- `contractCall` — Execute — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/contractcall.md
- `prepareContractTransaction` — Execute — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/preparecontracttransaction.md
- `prepareERC1155SetApprovalForAll` — Execute — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/prepareerc1155setapprovalforall.md
- `prepareERC721SetApprovalForAll` — Execute — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/prepareerc721setapprovalforall.md
- `signMessage` — Execute — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/signmessage.md
- `approveERC20` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/approveerc20.md
- `approveNFT` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/approvenft.md
- `ethSign` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/ethsign.md
- `prepareERC1155BatchTransfer` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/prepareerc1155batchtransfer.md
- `prepareERC20Approval` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/prepareerc20approval.md
- `prepareTransaction` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/preparetransaction.md
- `safeBatchTransferERC1155` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/safebatchtransfererc1155.md
- `safeTransferERC1155` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/safetransfererc1155.md
- `safeTransferERC721` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/safetransfererc721.md
- `sendSignedTransaction` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/sendsignedtransaction.md
- `sendTransaction` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/sendtransaction.md
- `sendTransactionWithOptions` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/sendtransactionwithoptions.md
- `transferERC20` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/transfererc20.md
- `transferERC721` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/transfererc721.md
- `transferFromERC20` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/transferfromerc20.md
- `transferNFT` — Financial — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/transfernft.md
- `loadWallet` — Other — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/loadwallet.md
- `checkWalletExists` — Read — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/checkwalletexists.md
- `erc1155_balanceOf` — Read — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/erc1155-balanceof.md
- `erc1155_balanceOfBatch` — Read — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/erc1155-balanceofbatch.md
- `erc1155_uri` — Read — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/erc1155-uri.md
- `erc20_balanceOf` — Read — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/erc20-balanceof.md
- `erc20_getTokenInfo` — Read — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/erc20-gettokeninfo.md
- `erc721_balanceOf` — Read — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/erc721-balanceof.md
- `erc721_tokenURI` — Read — https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server/erc721-tokenuri.md
- …and 38 more: https://policylayer.com/tools/crazyrabbitltc-mcp-ethers-server.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=crazyrabbitltc-mcp-ethers-server · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/crazyrabbitltc-mcp-ethers-server