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

Goes well beyond the annotations (readOnlyHint=false, destructiveHint=false) by disclosing a hard quota cost ('50 units of a small daily quota shared by all Adeli users'), the side effect that the comment is public, and a required confirmation step with the user. These are exactly the operational facts an agent cannot infer from the schema.

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?

Four compact sentences, front-loaded with the two call modes before platform conditions, quota cost and the public-visibility warning. Every sentence contributes a distinct constraint; nothing is restated from the title or annotations.

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?

Covers mode selection, platform requirements, quota cost and the safety warning, which is nearly everything needed for a write tool with no output schema. It stops short of indicating what the call returns (e.g. the created comment's ID) or how to recover from a quota failure.

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 only 33%, so the description carries real weight: it defines parentId as the reply target and postId as the own-post target, and notes postId is also required for TikTok/YouTube replies. It does not address message length limits, platform enum values, or profileId, leaving some parameters to the schema alone.

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 and resource ('Reply to a comment', 'comment on one of the account's own posts') and names the exact parameters that select each mode. It is clearly distinguishable from siblings like update_comment, delete_comment and list_comments without opening any schema.

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?

Explicitly tells the agent when to supply parentId versus postId-only, and adds platform-specific conditions ('TikTok and YouTube also need postId for a reply'). It does not name alternative siblings for correcting or removing a comment, but the mode-selection guidance is unambiguous.

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