imap_download_attachment

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

With no annotations, the description fully carries the behavioral burden. It explains behavior per file type: images returned inline, PDFs saved with optional text extraction, other files saved to downloads or custom savePath. No destructive actions are mentioned, and it appears consistent with a read operation.

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?

Three sentences, each essential and front-loaded. The first sentence defines the tool, the second explains behavior, the third gives usage guidance. No wasted words, and structure is logical.

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?

Given 7 parameters, no output schema, and no annotations, the description covers key behavioral aspects and usage. It references related tool for listing. Missing error handling details, but overall it's sufficient for an agent to select and invoke the tool correctly.

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 100%, so baseline is 3. The description adds value by explaining how file type affects behavior (e.g., 'extractText' for PDFs) and connects to imap_get_email for listing. This goes beyond the schema's parameter descriptions.

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?

The description clearly states the tool downloads a single attachment, specifying the required inputs (folder, uid, filename/contentId). It distinguishes between different file types and contrasts with just getting the message body, making the purpose unambiguous.

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?

The description explicitly says 'Use when the user wants the actual file contents, not just the message body,' providing clear usage context. It also references imap_get_email for listing attachments. While it doesn't list explicit when-not-to-use scenarios or alternatives beyond the implied contrast, the guidance is sufficient.

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