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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description's job is to add context, and it does: it discloses the pricing semantics (cheapest price per seller, i.e., not every price) and clarifies that `url` points to a page listing all sellers and prices. It does not mention behavior on an unknown matchId or how currency affects the returned prices, which keeps it short of a 5.

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 front-loaded with the payload contents and then the `url` clarification; no filler, no restatement of the title, and the most useful disambiguation (cheapest-per-seller vs. all prices) comes last as a targeted note.

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 carries the burden of describing return values and does so field by field, including the meaning of `url`. What remains uncovered is edge behavior (unknown matchId, empty travel directions) and how `currency` changes output, which is a modest gap for a simple two-parameter read tool.

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 both `matchId` and `currency` are already documented, including the fallback chain for currency. The description adds nothing about either parameter, 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?

"One match: kickoff, teams, competition, the cheapest price we hold at each ticket seller, the venue and any available travel directions" states the resource (a single match) and enumerates exactly what it returns, which makes it clearly the detail view rather than a search. It never names the sibling list tools (find_matches, find_matches_near), so the differentiation is inferred from "one match" 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?

There is no when-to-use or when-not guidance in the description; nothing tells the agent to call this after a search returns a matchId or to prefer find_matches for browsing. The only workflow hint, "The matchId another tool returned," lives in the schema, not the description.

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