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

Annotations already declare read-only, idempotent, closed-world, non-destructive, so the bar is lower, yet the description still adds substantial behavior: the free-tier cost model, the exact verification criterion (booked through NUM and scanned the venue's own code), exclusion of comped/partner guests, and the 5-rating publishing threshold below which all numbers are null with an explanatory `note`. That is context an agent could not infer from annotations.

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 core limitation and return shape are front-loaded in one dense paragraph with no filler topics. Minor waste in the redundant parenthetical 'free (included in the no-fee free tier)', but overall every clause carries real 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?

There is no output schema, so the description correctly documents the return surface: `external` with its `source`, `num_verified` with average/count/star distribution, the `note` on suppression, and the required `attribution`. Combined with the tier and eligibility rules, an agent has everything needed to call and correctly interpret the result.

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% and the single `place_id` parameter already documents its own provenance ('From search_places, place_details or directory_feed'), so the schema does the heavy lifting. The description adds no additional meaning about the parameter itself.

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 names a specific resource and verb-equivalent ('a rating SUMMARY for one place') and immediately scopes what it is NOT: no review text, no reviewer identities. This distinguishes it from the review-like expectations set by its name 'get_reviews', though it never explicitly contrasts with sibling tools like place_details or open_places.

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?

Usage is implied rather than stated: you fetch ratings for a known place. There is real guidance on how to use the output ('Keep the two numbers separate; do not average them together') and a hard requirement ('You MUST display the returned attribution'), but nothing says when to pick this over place_details or directory_feed.

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