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

Annotations already cover safety (readOnly, idempotent, non-destructive), and the description adds genuinely new behavior: only text and target are returned, attachments never are. The terminal 'Read-only' restates the annotation rather than adding to it, and pagination behavior remains unstated.

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?

One front-loaded sentence with a parenthetical clarifying status, followed by a short output caveat. No filler, and the most decision-relevant information (what is pending) comes first.

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 two-parameter read tool with no output schema, the description covers resource scope, status semantics, and returned fields. The one meaningful gap is the untested `limit` parameter, which an agent must guess at.

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 coverage is 0%, so the description must carry both parameters. It explains the status axis well by mapping semantic meaning onto each enum value (pending = awaiting approval, others = past states), but says nothing about `limit` or default result sizing, leaving half the surface undocumented.

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?

States a specific resource scope (replies, new chats, posts, comments, private replies awaiting approval) rather than a generic 'list'. The pending-vs-past framing plus the content types distinguish it from siblings like list_comments or list_messages.

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 makes the two usage modes explicit: default to items awaiting approval (pending), or query historical items by status. It gives clear calling context but names no alternatives or exclusions, so an agent must infer that other list_* tools cover non-approval content.

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