Frontier-Compute/zcash-mcp

decode_memo

Decode Zcash shielded memo fields, including ZAP1 typed memos, ZIP 302, plain text, and raw binary.

Instructions

Decode a Zcash shielded memo field. Handles ZAP1 typed memos, ZIP 302, plain text, and raw binary.

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": {
      "memo": "<memo>"
    },
    "name": "decode_memo"
  }
}

Input Schema

Name	Required	Description	Default
`memo`	Yes	Memo data as hex string or base64 (max 1024 bytes decoded)

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.2.2Apr 3, 2026

TDQS

A3.9/5.0

Behavior3/5

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

No annotations are provided, so the description carries full burden. It discloses supported input formats and encoding, but does not describe the output format or error behavior. For a decode tool, it could mention that it is read-only and what the return value looks like.

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 a single, well-structured sentence of about 20 words. It starts with the main purpose, then lists supported formats. No redundant or extra information.

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?

Given no output schema, the description could clarify the return format (e.g., decoded text or structured data). It also lacks mention of error handling. However, it adequately covers the core functionality and input variants for a simple decode tool.

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?

The schema already describes the 'memo' parameter as hex/base64 with a max size. The description adds value by specifying the types of memos handled (ZAP1, ZIP 302, plain text, raw binary), which enriches the understanding of what the decode operation covers.

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 the action ('Decode') and the resource ('Zcash shielded memo field'). It lists specific formats (ZAP1, ZIP 302, plain text, raw binary), distinguishing it from sibling tools which cover different functionalities.

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

Usage Guidelines3/5

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

The description implies usage for decoding various memo formats but does not explicitly state when to use it or when not to. No alternatives are mentioned, though sibling tools don't include another memo decoder.

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