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

With no annotations, the description carries the full burden and does some real work: it discloses ranking basis (post count), the engagement metrics attached, and that computation happens server-side mirroring the dashboard chart. It is silent on cost/credits (relevant given siblings like get_cost_estimate and get_credit_balance), on whether this is strictly read-only, and on performance or limits for large profiles.

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 sentences, front-loaded with the purpose before the return shape and the scoping note; every clause is substantive. The final sentence largely duplicates the schema's `scope` description, a small redundancy.

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?

There is no output schema, and the description compensates well by naming the returned fields and their ranking. Parameters are covered by the schema. It stops short of stating default time-window behavior for date_from/date_to or credit implications, which is a modest gap for an analytics call on 6 parameters.

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%, so all six parameters are already documented; the description only echoes `scope` as a post_collections.id and the notion of 'top N'. It adds no clarification about bigram defaults, date-range behavior, or the interaction between n and the two lists, so the baseline of 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: 'Surface the most-frequent topics in a profile's posts, with engagement context,' and enumerates the return shape (unigrams, optional bigrams, avg_engagement, vs_baseline, sample_post_url). It does not explicitly differentiate itself from the nearby siblings get_posting_insights and preview_posting_insights, which is the only thing keeping it off a 5.

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?

The only guidance is 'Pass `scope` (a post_collections.id) to scope the analysis to a collection,' which restates the schema. There is no statement of when to prefer this over get_posting_insights or preview_posting_insights, and no prerequisites such as needing a profile_id from list_profiles (that hint lives only in the schema).

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