list-attachments

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

No annotations provided, so description carries full burden. It discloses the tool returns names, MIME types, sizes, and a count, and clarifies it does not return bytes. However, it does not mention idempotency, rate limits, or error behavior, which would improve transparency.

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?

Two sentences plus a 'Do not use' clause, front-loaded with usage and return description. No wasted words, structured with clear sections (Use when, Returns, Do not use when).

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 one parameter and existence of output schema, description covers the essential return values and prerequisites. Lacks details on ordering or pagination, but for a simple list tool it is mostly complete.

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?

Only one parameter 'id' with regex pattern. Description implies it is a message id but does not explicitly explain the parameter. Schema coverage is 0%, so description should compensate, but it only provides context indirectly. A minimal but adequate explanation.

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 specifies the tool enumerates a message's attachments by id, listing their names, MIME types, and sizes. It distinguishes from siblings like fetch-attachment and save-attachment by stating what this tool does not do (return bytes).

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?

Explicitly states when to use (before saving or fetching an attachment) and when not to use (for bytes). Provides a prerequisite: obtain message id from search-messages or list-messages. This guides correct invocation.

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