attachment

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

Warns about attacker-authored content and describes how different MIME types are handled (inline images, untrusted blocks, signed links, file paths). No contradictory annotations exist, and the safety context is valuable.

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?

Every sentence adds meaningful detail—behavior, safety, and return formats. No fluff or redundancy; length is justified by the security context.

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?

Covers return behavior and security, and references the prerequisite tool 'show'. Missing error cases or fallback instructions, but for a targeted attachment fetch, the essential context is present.

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?

The 'part' parameter is explained via reference to 'show's output', but the 'id' parameter is not described at all. Since half the required parameters lack semantic guidance, the score is below the baseline.

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?

Clearly states the verb 'Return' and the resource 'attachment or MIME part of a message'. Unambiguous and distinguishes from sibling tools that list or show content.

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?

Provides a precondition by referencing 'show's output' for the part number, but does not explicitly contrast with sibling tools like 'text' or 'files'. Still, the purpose is specific enough for an agent to select it.

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