# verify_document_hash

Find FreeSign receipts matching a local document SHA-256 hash.

Agent View of the PolicyLayer registry record for `verify_document_hash`. HTML page: https://policylayer.com/tools/com-free-sign-signing/verify-document-hash

## Facts

- Tool: `verify_document_hash`
- Server: FreeSign — Free e-signature (`https://free-sign.com/mcp`) — https://policylayer.com/tools/com-free-sign-signing.md
- Homepage: https://github.com/https://free-sign.com/mcp
- Risk category: Read (Low risk)
- Registry record: grade C, identity unverified
- Server auth posture: open
- Server CORS policy: *
- Server rate-limited: no
- Parameters: 1 (1 required)
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `document_sha256` | string | yes |  |

Parameters from the server's own tool schema.

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

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "verify_document_hash",
    "arguments": {
      "document_sha256": "<document_sha256>"
    }
  }
}
```

## Why verify_document_hash is rated Low

This tool performs a read-only lookup of existing signing receipts. It retrieves data without modifying, deleting, or executing operations. The hash lookup is a search operation analogous to a database query. Even though the server handles e-signatures (legally significant), this specific tool only reads/verifies records rather than creating signatures or financial transactions.

From the tool's own definition: "Tool description states 'Find FreeSign receipts matching a local document SHA-256 hash' — a pure query/lookup operation that retrieves matching receipts based on a hash input."

## Use case

AI agents call verify_document_hash to retrieve information from FreeSign — Free e-signature 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 FreeSign — Free e-signature:

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

## Other tools on FreeSign — Free e-signature (4)

- `get_ots_proof` — Read — https://policylayer.com/tools/com-free-sign-signing/get-ots-proof.md
- `get_receipt` — Read — https://policylayer.com/tools/com-free-sign-signing/get-receipt.md
- `verify_audit_chain` — Read — https://policylayer.com/tools/com-free-sign-signing/verify-audit-chain.md
- `create_signing_envelope` — Write — https://policylayer.com/tools/com-free-sign-signing/create-signing-envelope.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-free-sign-signing · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/com-free-sign-signing