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

Annotations already declare readOnlyHint=true, and the description adds valuable scope context: it covers both the user's own posts and third-party posts fetched via fetch_post_engagers. It also discloses the return payload shape (count, truncated, engagements array). It does not contradict the annotations, though it omits rate-limit or auth details.

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?

The description is well-structured with separate summary and returns sections, and it front-loads the most important scoping sentence. The column list is compact and useful, and there is no filler or redundant restating of the tool name.

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 query tool with no required parameters, this description covers scope, usage, chaining, column semantics, and return shape. Paging and ordering are documented in the schema, so nothing an agent needs to call this tool correctly is missing.

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%, so the baseline is 3. The description adds meaning beyond the schema by explaining that post_id corresponds to post_analytics_id from fetch_post_engagers and by defining reaction_value semantics such as 'empty for comments,' which is not present in the input schema.

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 opens with a specific verb and resource: 'Query individual reactions/comments on tracked LinkedIn posts.' It further distinguishes this tool from query_linkedin_posts by clarifying it returns engagement-level rows, not posts, and it references fetch_post_engagers as the upstream source.

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?

Provides explicit use cases ('find warm leads, identify who engaged with specific posts, or filter engagers by role/company') and chaining guidance with query_linkedin_posts and fetch_post_engagers. It doesn't explicitly state when not to use this tool in favor of a sibling, but the examples make the intended context clear.

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