add_attachment

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only states the action ('Add') without detailing permissions, return value, idempotency, or side effects. This is a minimal disclosure, comparable to the update_drive example.

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 concise with two short sentences, but it is slightly redundant—the second sentence restates the first with URL specificity. It is front-loaded and free of unnecessary words, earning a 4.

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 tool has 5 parameters and no output schema, and the description is minimal. It does not explain what the tool returns, any prerequisites (like the cardId), or how the fields/detailLevel parameters affect the response. This leaves a significant gap in context for the agent to invoke it 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 description coverage is 100%, so the baseline is 3. The description adds no additional meaning beyond what the schema already provides—the 'attach a URL' phrase simply echoes the url parameter description. No extra compensation is needed, hence a 3.

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's function with a specific verb and resource: 'Add an attachment to a card' and further specifies it attaches a URL to a card. This distinguishes it from sibling tools like get_attachments and delete_attachment.

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 includes an explicit usage instruction ('Use this tool to attach a URL to a card'), which clearly identifies the intended scenario. However, it does not mention when not to use it or alternative tools, though none exist for adding attachments.

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