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

Annotations already declare read-only, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds genuine context beyond that: prices are identical to quote_route, and each grid cell carries its own buy_url, which tells the agent what it gets back despite there being no output schema. It does not mention cost of a wide grid or any rate/size caveats beyond the caps already in the schema.

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?

Two sentences, both load-bearing: the first front-loads the grid shape and caps, the second covers the pricing source and per-cell output. No filler and nothing repeated from the title.

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 six parameters, full schema coverage, and complete annotations, the remaining burden is explaining what a call returns — and the buy_url-per-cell sentence does that without an output schema. An agent could call this correctly; only an explicit contrast with quote_route 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 description coverage is 100%, so the schema already explains route, days, gb, bucket, currency, and language. The description only restates the max-8 days and max-6 gb caps and gives one example ('e.g. to compare with other providers'), adding little meaning beyond the field descriptions. Baseline 3 is appropriate.

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 ('the same route priced') plus the exact grid dimensions it returns: several trip lengths (days, max 8) by several pool sizes (gb, max 6) in one call. That is enough for an agent to tell it apart from the single-price sibling quote_route, which the description explicitly references as the per-quote equivalent.

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 two concrete situations to use it: 'to compare with other providers' and 'to find the best fit'. It also implies the relationship to quote_route ('same server prices as quote_route'), though it never states the inverse condition — when a single quote is preferable to the grid — so the routing guidance is clear but not complete.

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