Skip to main content
Glama

get_attachment

Retrieve email attachments from Gmail messages using message and attachment IDs to access files sent in emails.

Instructions

Get a message attachment

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
messageIdYesID of the message containing the attachment
idYesThe ID of the attachment

Implementation Reference

  • Shared helper function handleTool that manages OAuth2 authentication and Gmail client creation for all tools, including get_attachment.
        const oauth2Client = new OAuth2Client({
          clientId: credentials?.clientId,
          clientSecret: credentials?.clientSecret,
          redirectUri: `http://localhost:${AUTH_SERVER_PORT}/oauth2callback`
        })
    
        if (credentials?.refreshToken) oauth2Client.setCredentials({ refresh_token: credentials.refreshToken })
    
        return oauth2Client
      } catch (error: any) {
        return null
      }
    }
    
    export const launchAuthServer = async (oauth2Client: OAuth2Client) => new Promise((resolve, reject) => {
      const server = http.createServer()
Behavior2/5

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. 'Get' implies a read operation, but the description doesn't specify if this requires authentication, what happens if IDs are invalid, or what the output format might be (e.g., file content vs. metadata). This leaves significant gaps for a tool that likely interacts with user data.

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, efficient sentence ('Get a message attachment') that is front-loaded and wastes no words. Every part of it contributes directly to understanding the tool's purpose, making it highly concise and well-structured.

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

Completeness2/5

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

Given the complexity of accessing attachments (likely involving binary data or metadata), no annotations, and no output schema, the description is incomplete. It doesn't explain what is returned (e.g., file content, download link, or attachment details), leaving the agent uncertain about the tool's behavior and output.

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?

The input schema has 100% description coverage, with clear parameter descriptions ('ID of the message containing the attachment' and 'The ID of the attachment'). The tool description adds no additional semantic context beyond what the schema provides, so it meets the baseline of 3 for adequate but minimal value.

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?

The description 'Get a message attachment' clearly states the verb ('Get') and resource ('message attachment'), making the purpose immediately understandable. However, it doesn't differentiate from sibling tools like 'get_message' or 'get_draft' that might also retrieve message-related content, so it's not fully specific about what distinguishes this tool.

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?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing a message ID and attachment ID), exclusions, or how it differs from other 'get_' tools in the sibling list, leaving the agent to infer usage from the tool name alone.

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

Install Server

Other Tools

Latest Blog Posts

MCP directory API

We provide all the information about MCP servers via our MCP API.

curl -X GET 'https://glama.ai/api/mcp/v1/servers/HitmanLy007/gmail-mcp'

If you have feedback or need assistance with the MCP directory API, please join our Discord server