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

Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true and openWorldHint=true, so the safety profile is covered by structured data. The description's main behavioral addition is the unanswered-only default, but that duplicates the schema's unansweredOnly default rather than revealing anything new; ordering, pagination, and per-platform coverage are left 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?

Three short sentences, front-loaded with the core action, followed by default behavior, then the paired action tool. No filler, no repetition of the tool title.

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 read-only, annotation-covered, fully documented-schema list tool with no output schema, the description covers purpose, default filtering, and the natural next step. Minor gaps: recency ordering is only implied by 'recent', and multi-platform aggregation behavior (single platform vs all) isn't spelled out.

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 100%: limit, platform, and unansweredOnly are all documented inline with defaults, ranges, and an enum. The description restates only the unansweredOnly default and adds nothing about limit semantics or platform enum behavior, 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 and resource ('Read recent comments') with the scope ('on the user's social media posts across platforms'), which cleanly separates it from siblings like list_reviews, list_conversations, and list_comment_automations. It also names the write-side counterpart (reply_to_comment), so an agent can tell read from respond without opening a 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?

Gives clear default context ('By default returns only unanswered comments') and routes the follow-up action to reply_to_comment, which is exactly what an agent needs after listing. It stops short of when-not-to-use guidance (e.g., that clearing the unansweredOnly flag is required to see already-answered comments or the full stream).

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