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

Annotations already declare readOnlyHint=false, destructiveHint=false, idempotentHint=false, and openWorldHint=false, so the safety and mutation profile is covered. The description adds the auth scope requirement, which is genuinely useful context beyond annotations, but says nothing about return behavior, error/duplicate handling, or side effects.

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 short sentences with the core action front-loaded and no filler. Given the size of the input schema, it is arguably under-specified rather than overlong, but it wastes no words.

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 creation tool with 27 parameters and no output schema, the description is very thin: it omits what a successful call yields (created site ID?), whether all fields are optional except name, and any deduplication or validation behavior. Annotations and the schema cover much, but the description leaves an agent without a full behavioral picture.

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% across all 27 parameters, so the schema already documents each field including the required 'name'. The description adds no parameter-level meaning or grouping (e.g., address vs. lease vs. insurance blocks), so baseline 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?

States a specific verb ('Create') and resource ('site'), so the agent knows exactly what it does. However, with hundreds of 'create_*' siblings (create_building, create_location, create_project_site), it offers no differentiation or disambiguation about which entity a 'site' is versus adjacent resources.

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?

Aside from the authorization prerequisite ('Requires sites:write scope'), there is no guidance on when to use this versus alternatives. It does not mention related tools like bulk_create, update_site, or create_site variants, nor any preconditions such as unique name requirements.

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