save_attachment

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

The description discloses the primary side effect (writing to disk) and the return value (written file path). Annotations only include destructiveHint:false, so the description adds context about the side-effect nature. However, it does not clarify the relationship between saveTo and outputPath, which could confuse users about behavior. No contradiction with annotations.

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?

The description is three sentences, with the first sentence stating the core action, the second giving usage context, and the third pointing to an alternative. Every sentence is purposeful and there is no fluff.

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?

The description covers the primary purpose and basic usage, and it differentiates from a key sibling. However, it lacks clarity on the two optional path parameters and does not describe the return format beyond 'written file path' (e.g., whether it includes size). The absence of an output schema makes these gaps more consequential.

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 descriptions cover 100% of parameters, but the descriptions of saveTo and outputPath are overlapping and ambiguous. The tool description does not clarify the distinction, leaving users uncertain which to use. This undermines parameter semantics despite high coverage.

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 identifies the tool's function as saving a single attachment to disk using attachmentId and returning the file path. It distinguishes from the sibling save_attachments by emphasizing 'single' and 'specific attachmentId'. This gives a specific verb, resource, and scope.

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?

It explicitly states when to use this tool—when you have a specific attachmentId from list_attachments—and when to prefer save_attachments (for all/filtered attachments). This is a clear alternative-guiding statement.

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