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

Annotations already declare readOnlyHint and non-destructive, so safety is covered. The description adds real value beyond them by disclosing the auth requirement ('Cotlet API key with access to this app') and the shape of the returned discussion (replies nested under parent comment).

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?

Front-loads the key point, but the first and second sentences largely restate each other ('title, body, attachments and the comment tree' vs 'full body, attachments (images, files, links) and the whole comment tree'). One sentence could carry the content without losing information.

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, the description correctly carries the return-shape burden by describing the post fields and nested comment structure, and it notes the auth requirement. Complete enough for a simple two-parameter read tool.

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 100% and both parameters are documented in the schema (group URL name, post_id from list_posts). The description adds no syntax or format guidance beyond the schema, so the baseline 3 applies.

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 verb (get) and resource (post) and enumerates scope: full body, attachments, and nested comment tree. 'Returns one post' implicitly contrasts with skool_list_posts, so an agent can distinguish the singular-fetch tool from the listing sibling.

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?

Gives explicit usage context: 'Use it before replying so your agent sees the full discussion.' This tells the agent when it's valuable, but doesn't name alternatives (e.g. skool_comment_on_post) or state any when-not conditions.

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