add_attachment

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

Annotations already declare readOnlyHint=false and destructiveHint=false, and the description consistent with these does not contradict them. It adds the context that the file is local, which is a useful distinction, but does not disclose other behavioral traits like potential file uploads or side effects on the draft.

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 a single, front-loaded sentence that directly states the tool's purpose without any filler. Every word earns its place, making it highly concise and appropriately structured for a simple tool.

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 the simple nature of the tool (two self-explanatory parameters, annotations provided, no output schema), the description is largely sufficient for basic invocation. It clearly identifies the action and target, though it could benefit from noting that the draft must already exist or that this modifies an existing draft.

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 description coverage is 0%, so the description must compensate for explaining parameters. It only marginally clarifies that file_path refers to a local file, but provides no details on format, constraints, or how draft_id and file_path are used beyond what their names imply.

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 'Attach a local file to a draft' states a clear verb (Attach) and resource (local file to a draft), distinguishing it from sibling tools like list_attachments and download_attachment. The action is unambiguous and aligns with the tool name.

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 provides no guidance on when to use this tool versus alternatives such as create_draft or update_draft, and does not mention prerequisites (e.g., the draft must exist) or edge cases. It simply states the action without usage context.

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