io.github.daedalus/mcp-cryptography

Overview Schema Source Related Servers Discussions Admin

scrypt_derive

Derive a cryptographic key from a password using Scrypt, with optional hex-encoded salt. Returns derived key and salt as hex.

Instructions

Derive key using Scrypt.

Args: password: Password to derive from. salt: Hex-encoded salt (optional, will generate if not provided).

Returns: Dictionary with 'derived_key' (hex) and 'salt' (hex).

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "password": "<password>"
    },
    "name": "scrypt_derive"
  }
}

Input Schema

Name	Required	Description	Default
`salt`	No
`password`	Yes

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.1Jul 30, 2026

TDQS

A3.5/5.0

Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are present. The description does not disclose important behavioral details such as whether the function is deterministic (if no salt), default cost parameters (N, r, p), or security implications. It omits side effects and mutation behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is minimal and well-structured with a title, Args section, and Returns section. Every sentence provides necessary information without redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The description explains the return value (dictionary with derived_key and salt) adequately for a simple key derivation. However, it lacks details on Scrypt parameters (N, r, p) and how the salt is generated when omitted, which are important for security context.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0%, but the description explains both parameters: 'password' as the input to derive from and 'salt' as optional hex-encoded string. It adds value beyond the schema types, though it could include constraints like length or encoding requirements.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states 'Derive key using Scrypt.' as the action and algorithm. It specifies the function (key derivation) and the method (Scrypt), distinguishing it from siblings like hash functions or PBKDF2.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidelines are provided on when to use Scrypt versus alternatives like pbkdf2_derive. The description lacks context for selection, such as security requirements or performance considerations.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.