get_unread

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

No annotations are provided, so the description must carry the burden. It discloses that it lists unread messages and orders them newest first, which is basic behavior. It does not disclose potential side effects (likely none for a read operation), or details about pagination, but given the simple nature, this is adequate.

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 extremely concise: one sentence that conveys the action, resource, and ordering. No unnecessary words. Front-loaded with the core purpose.

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?

For a simple list operation with one parameter and no output schema, the description is adequate. It doesn't explain the return format or fields, but the tool is simple and the schema covers the input. Given the low complexity, this is acceptable, though slightly more detail about the output could be helpful.

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 schema description covers 100% of the parameter (limit) with a clear explanation of default value. The description doesn't add extra information about the parameter, but the schema already provides sufficient meaning, so baseline 3 is appropriate.

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 action ('List received messages'), the specific resource ('not been read yet'), and the ordering ('newest first'). It distinguishes from siblings like get_messages (which likely returns all messages) and search_messages (which filters by query).

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 implies when to use this tool (when needing unread messages) and explicitly states the ordering. However, it doesn't explicitly mention alternatives or when not to use it, but the purpose is clear enough to infer the use case from the sibling list.

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