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

Annotations already cover readOnly, idempotent and non-destructive, but the description adds genuinely non-obvious behavior: no Desk Pass required and the call does not count against the account's daily or monthly limit. It also discloses a fallback ('A page read_docs does not hold is answered with the pages it holds'), which prevents an agent from treating a miss as an error.

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 core action, then scope, then parameter hint, then cost profile — a sensible order with no filler. The multi-item list of doc topics is slightly long, but it is the one place where extra length helps an agent decide whether the tool can answer a question.

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 three-optional-parameter read tool with no output schema, the description covers purpose, scoping, fallback behavior and the quota exemption. Return shape is only sketched ('word for word', matching sections), which is the one remaining gap an agent might want.

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%, and each parameter is already well documented in the schema, including examples and the `asked` verbatim rule. The description only restates which params to pass ('Pass `about`... and `pages` for a page you know'), adding little beyond the schema.

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?

States a specific verb and resource ('Reads The Tennis Desk's own docs, word for word') and enumerates what the docs cover, so an agent knows exactly what content it returns. It explicitly separates itself from the rest of the toolset by scope: 'when someone asks about the Desk itself rather than a team, a player or a match.'

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 a clear trigger condition and an implicit exclusion (anything about a team, player or match goes elsewhere), plus guidance on passing `about` for topic search versus `pages` when a page is known. It does not name a specific sibling alternative such as read_research, so the routing is by exclusion rather than explicit hand-off.

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