# list_supported_formats

List all supported file formats that can be faxed.

Agent View of the PolicyLayer registry record for `list_supported_formats`. HTML page: https://policylayer.com/tools/com-gotfreefax-mcp/list-supported-formats

## Facts

- Tool: `list_supported_formats`
- Server: GotFreeFax (`https://www.gotfreefax.com/mcp`) — https://policylayer.com/tools/com-gotfreefax-mcp.md
- Homepage: https://github.com/vannet/gotfreefax-mcp
- Risk category: Read (Low risk)
- Registry record: grade D, identity unverified
- Server auth posture: open
- Server CORS policy: *
- 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": "list_supported_formats",
    "arguments": {}
  }
}
```

## Why list_supported_formats is rated Low

This tool retrieves metadata about supported formats without modifying, deleting, or executing any operations. It poses minimal security risk as it only provides informational data about system capabilities. The low severity reflects the absence of any potential for misuse—an AI agent calling this tool cannot cause harm regardless of how it uses the returned information.

From the tool's own definition: "Tool name 'list_supported_formats' and description 'List all supported file formats' indicate a retrieval operation with no side effects. The verb 'list' is a classic Read operation that queries available data."

## Use case

AI agents call list_supported_formats to retrieve information from GotFreeFax 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 GotFreeFax:

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

## Other tools on GotFreeFax (6)

- `purchase_credits` — Financial — https://policylayer.com/tools/com-gotfreefax-mcp/purchase-credits.md
- `send_fax` — Financial — https://policylayer.com/tools/com-gotfreefax-mcp/send-fax.md
- `check_fax_status` — Read — https://policylayer.com/tools/com-gotfreefax-mcp/check-fax-status.md
- `get_account_balance` — Read — https://policylayer.com/tools/com-gotfreefax-mcp/get-account-balance.md
- `list_sent_faxes` — Read — https://policylayer.com/tools/com-gotfreefax-mcp/list-sent-faxes.md
- `send_free_fax` — Write — https://policylayer.com/tools/com-gotfreefax-mcp/send-free-fax.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=com-gotfreefax-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/com-gotfreefax-mcp