himalaya-mcp

Overview Schema Source Related Servers Discussions Admin

download_attachment

Downloads a specified email attachment to a temporary directory and returns its file path, so you can access the file from the email message.

Instructions

Download an email attachment to a temporary directory. Downloads all attachments, then returns the path to the requested file.

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": {
      "id": "<id>",
      "filename": "<filename>"
    },
    "name": "download_attachment"
  }
}

Input Schema

Name	Required	Description
`id`	Yes	Email message ID
`folder`	No	Folder name (default: INBOX)
`account`	No	Account name (uses default if omitted)
`filename`	Yes	Attachment filename to download

Schema Changelog

Changes observed during successful MCP inspections.

Changed2 schema fields changedv2.2.2Nov 7, 2026

addedInput schema / properties / id / anyOf

Added value: +[
+  {
+    "type": "string"
+  },
+  {
+    "maximum": 9007199254740991,
+    "minimum": 0,
+    "type": "integer"
+  }
+]

removedInput schema / properties / id / type
```
Removed value: -"string"
```

First observedv1.7.0Jun 21, 2026

TDQS

C2.9/5.0

Behavior2/5

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

No annotations are supplied, so the description carries the full disclosure burden. It does add valuable behavior — a filesystem write to a temp directory and the fact that ALL attachments are fetched regardless of the single filename requested — but omits permission/account requirements, overwrite behavior, temp-file lifetime, and what happens if the filename does not exist.

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

Conciseness4/5

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

Two short sentences with the action and side effect front-loaded; nothing superfluous. The phrase 'the requested file' is slightly loose where 'the file matching filename' would be sharper, but the passage is efficient overall.

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?

With no output schema, the description correctly compensates by stating the return value (a path), which is the key missing piece. However, for a tool with no annotations and a side-effecting filesystem write, it should also cover error behavior for missing attachments and where/how long the temp file persists.

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

Parameters3/5

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

Schema description coverage is 100%, so id, folder, account, and filename are already documented in the schema. The description only indirectly hints at the filename parameter ('the requested file') and does not clarify that folder/account scope the message lookup, so it adds little beyond the schema baseline.

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

Purpose4/5

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

States a specific verb and resource ('Download an email attachment') plus the destination ('temporary directory'), which is more precise than the sibling list_attachments. It does not explicitly name list_attachments as the discovery step before downloading, so sibling differentiation is only implied.

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?

There is no explicit when-to-use guidance, no prerequisites (e.g., 'call list_attachments first to obtain a valid filename'), and no exclusion versus alternatives such as read_email or export_to_markdown. The agent must infer the workflow entirely from the purpose sentence.

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