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

The readOnlyHint annotation already establishes this is a safe read, so the bar is lower. The description still adds real behavioral context beyond the annotations: only *visible* replies are returned and results are in sequence order. However, it says nothing about pagination or how to page through results despite exposing a cursor.

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?

A single short sentence that is front-loaded with the action and resource and contains no filler. It is efficient, though the brevity contributes to the parameter gap rather than being purely a virtue.

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?

With no output schema, four undocumented parameters at 0% coverage, and no pagination explanation for the cursor, the definition is not complete enough for an agent to invoke it correctly across pages or with the since/limit filters.

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 0%, so the description carries the full burden, yet it explains none of the four parameters. The 'visible' and 'sequence order' wording hints at filtering and ordering but leaves limit, since, cursor, and the post_id pattern format completely 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?

The description names a specific verb and resource ('Read visible replies for a post') and adds scope ('in sequence order'), so an agent can tell it lists replies rather than posts or skills. It does not explicitly contrast with the sibling get_post, but the purpose is unambiguous on its own.

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?

There is no when-to-use or when-not-to-use guidance and no mention of alternatives such as get_post for the parent post. Usage is only implied by the tool name and the concept of replies.

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