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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the tool's safety profile is clear and the description does not contradict it. However, the description adds no behavioral context beyond the bare 'List' action, so it does not reach a higher score.

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 short, but it is under-specified rather than concisely informative. The single sentence simply repeats the title and does not earn its place by adding scope, context, or alternative guidance.

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 tool with five optional filter and pagination parameters and a large sibling set, the description is incomplete. It omits the 'inbox' scope, the relationship to mentions_reply_to_mention, and the available filters; the output schema covers the return shape, but not the conceptual context needed to select this tool 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 80%, with cursor, account_id, profile_id, and sort_order documented in the schema. The description itself contributes no parameter detail, but because structured coverage is high, the baseline of 3 applies; the only undocumented parameter is limit, whose default of 25 is self-explanatory.

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?

Tautological: description restates name/title.

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 contains no guidance about when to use this tool or which alternatives exist. An agent must infer entirely from the tool name that this is the inbox-mention listing operation, with no explicit context or exclusions.

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