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

Annotations already cover read-only, idempotent, non-destructive, and closed-world behavior. The description goes beyond them by disclosing that amount fields are bare numbers with no currency and by prescribing a cross-tool call to get_organization_settings before stating a currency value—useful operational context that annotations do not provide.

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 tightly written sentences with no filler. The purpose is front-loaded, and the currency-handling note is concise and actionable; nothing needs to be trimmed.

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 simple list tool with rich annotations and full schema coverage, the description supplies the essential purpose and a key return-value caveat. It does not explain the shape of a site record (there is no output schema) or clarify the site/location boundary, but what is present is enough to invoke the tool safely.

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 city, page, search, and per_page are fully documented in the schema itself. The description adds no parameter-level meaning, making the baseline of 3 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?

States a clear verb and resource ('List sites'), defines sites as physical locations/campuses, and scopes to the organization. However, it does not distinguish list_sites from sibling list_locations or list_buildings, leaving ambiguity about what a 'site' is versus a 'location'.

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?

The description implies usage by starting with 'List all sites' and gives a specific follow-up instruction for currency, but it never states when to choose list_sites over alternatives like list_locations or get_site, nor does it mention exclusions. Guidance is therefore implied rather than explicit.

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