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

Consistent with readOnlyHint=true — nothing implies mutation. Beyond the annotation it discloses the sort order (newest updates first), the response envelope (summary.meta with count/pages, reviews[] with ratings, comment text, customer display name, threads), and how to paginate, which the annotations do not cover.

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?

Front-loads the action and ordering, then packs mode semantics and return shape into two compact sentences with no filler. The mode clause is a dense run-on but each segment carries distinct information.

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 17-parameter, no-output-schema read tool, the description covers the essentials: what's returned, how to page, and the mode/sku dependency. It does not address default `since_period` behavior relative to `since_updated_period`, but that gap is minor given 94% schema coverage.

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 94%, so the schema already documents most of the 17 parameters including the conditional SKU requirement. The description mostly echoes that (mode values, product_sku/parent_product_sku dependency) rather than adding new semantics such as default-period interactions or filter interplay.

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?

Opens with a specific verb+resource ("List reviews of your Feefo account") plus an ordering guarantee ("newest updates first"), and the mode enumeration establishes the breadth vs the single-review siblings. It never names feefo_get_review or feefo_get_review_summary, so the distinction from those siblings is left inferential rather than stated.

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 concrete conditional guidance: mode=product requires product_sku or parent_product_sku, and each mode's meaning is spelled out so an agent can pick one. It stops short of saying when to prefer this over feefo_get_review or feefo_get_review_summary (e.g. bulk retrieval vs single-record fetch).

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