Saves a Gmail attachment to the attachment folder under a new unique name and returns its local path, so you can work with the file locally.
Save an attachment to the attachment folder under a new unique name and return the local path.
| Name | Required | Description | Default |
|---|---|---|---|
| filename | Yes | ||
| message_id | Yes | ||
| attachment_id | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must carry behavior, and it does disclose two non-obvious traits: the file is written into an 'attachment folder' and renamed to a unique name rather than kept as-is, and the local path is returned. It omits failure modes, overwrite/collision behavior, permission needs, and whether the original filename is preserved anywhere.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
One sentence, front-loaded with the action and ending with the return value. No filler or redundant restatement of the tool name.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
An output schema exists, so return-value detail is unnecessary, and the description correctly summarizes the path return. However, for a file-writing mutation with zero annotation coverage and completely undescribed parameters, it leaves too much unsaid about preconditions and side effects.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 0%, so the description must compensate; it adds the meaningful semantic that 'filename' is a base for a renamed artifact rather than the resulting file name. It says nothing about message_id or attachment_id, leaving two of three required parameters undocumented.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb (save), the resource (attachment), and the outcome (new unique name plus local path returned). It is distinguishable from read-oriented siblings such as get_message, though it never explicitly names how it relates to attachment retrieval via those siblings.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
No guidance on when to use this versus get_message or other siblings, and no prerequisites stated (e.g., that the IDs come from a message). The agent must infer the workflow entirely from the parameter names.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.