# sha384

Calculate SHA-384 hash of a string

Agent View of the PolicyLayer registry record for `sha384`. HTML page: https://policylayer.com/tools/1595901624-crypto-mcp/sha384

## Facts

- Tool: `sha384`
- Server: Crypto_MCP (`1595901624/crypto-mcp`) — https://policylayer.com/tools/1595901624-crypto-mcp.md
- Homepage: https://github.com/1595901624/crypto-mcp
- Risk category: Read (Low risk)
- Registry record: grade A, 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": "sha384",
    "arguments": {}
  }
}
```

## Why sha384 is rated Low

This is a pure cryptographic hashing function. It reads input data and computes a one-way hash digest. Hash functions are deterministic, read-only operations with no side effects on stored data or external systems. The tool cannot reverse the hash, cannot modify data, and cannot trigger external operations.

From the tool's own definition: "Tool is named 'sha384' and described as 'Calculate SHA-384 hash of a string'. SHA-384 is a cryptographic hash function that produces a fixed-size digest from input data without modification to the original data."

## Use case

AI agents call sha384 to retrieve information from Crypto_MCP 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 Crypto_MCP:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "sha384": {}
  }
}
```

## Other tools on Crypto_MCP (13)

- `des_encrypt` — Execute — https://policylayer.com/tools/1595901624-crypto-mcp/des-encrypt.md
- `aes_encrypt` — Other — https://policylayer.com/tools/1595901624-crypto-mcp/aes-encrypt.md
- `aes_decrypt` — Read — https://policylayer.com/tools/1595901624-crypto-mcp/aes-decrypt.md
- `base64_decode` — Read — https://policylayer.com/tools/1595901624-crypto-mcp/base64-decode.md
- `base64_encode` — Read — https://policylayer.com/tools/1595901624-crypto-mcp/base64-encode.md
- `des_decrypt` — Read — https://policylayer.com/tools/1595901624-crypto-mcp/des-decrypt.md
- `hex_decode` — Read — https://policylayer.com/tools/1595901624-crypto-mcp/hex-decode.md
- `hex_encode` — Read — https://policylayer.com/tools/1595901624-crypto-mcp/hex-encode.md
- `md5` — Read — https://policylayer.com/tools/1595901624-crypto-mcp/md5.md
- `sha1` — Read — https://policylayer.com/tools/1595901624-crypto-mcp/sha1.md
- `sha224` — Read — https://policylayer.com/tools/1595901624-crypto-mcp/sha224.md
- `sha256` — Read — https://policylayer.com/tools/1595901624-crypto-mcp/sha256.md
- `sha512` — Read — https://policylayer.com/tools/1595901624-crypto-mcp/sha512.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=1595901624-crypto-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/1595901624-crypto-mcp