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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, and the description adds substantial behavior beyond them: sort order, the full status vocabulary, the meaning of can_reply (needs a connected GBP or Facebook page), and the empty-list-plus-note outcome for locations without a Reputation Manager report. That is exactly the kind of outcome and prerequisite context annotations cannot express.

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 scope and ordering are front-loaded in the first clause, and the second sentence carries the return fields and prerequisites without filler. The long parenthetical enumeration of status values is dense but earns its place by defining an otherwise opaque field.

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 usefully enumerates return fields and explains can_reply, and it covers the key prerequisite and empty-result case. The only gap is pagination behavior: it never mentions the next_cursor/limit loop, leaving that entirely to the schema field descriptions.

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 limit, cursor, rating, source and location_id are all documented in the schema itself. The description only echoes 'filter by rating and site' and adds no syntax, default, or edge-case guidance beyond that, 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?

The description states a specific verb and resource ('List a location's reviews from all tracked review sites'), plus ordering ('newest first') and the fields returned. It is clearly distinguishable from get_review_summary (aggregate) and respond_to_review (write) in the sibling list 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?

It gives real usage context: filter by rating and site, and the prerequisite that the location must have a Reputation Manager report (BrightLocal Grow plan with GBP or Facebook connected), including what happens when it does not. It stops short of naming alternatives such as get_review_summary for aggregate stats or respond_to_review for replying, so there is no explicit when-not-to-use.

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