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

Goes beyond the destructiveHint annotation by disclosing the write semantics, the non-idempotent duplicate-creation behavior, and the underlying endpoint. It does not cover permission/auth requirements for creating a site on behalf of a uid, or what happens with unknown fields, which would have pushed this higher.

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?

Three tight fragments, front-loaded with the WRITE marker, then the risk note, then the endpoint. No filler sentences and nothing buried mid-paragraph.

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 19-parameter create operation with no output schema and destructiveHint=true, the description covers the action and the duplication risk but omits the return value (e.g., the new site id), any auth/permission expectations, and any field-level guidance. Adequate to invoke, but not complete for a tool of this surface area.

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?

The description says nothing about any of the 19 parameters beyond implying that a site belongs to 'a user' (the required uid). With only 58% schema coverage, roughly eight fields (zip, beds, baths, city, state, garage, lotsize, yearbuilt) are undocumented in both places, and the description does not compensate.

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 ('create a new property site for a user') and pins the underlying operation ('API: POST /site'). Combined with the non-idempotency note, an agent can separate this from hdphotohub_update_site and hdphotohub_list_sites without opening any schema.

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?

'WRITE: create a new property site' plus 'a repeat call creates a second site' gives clear context for when this tool is appropriate and warns against retry loops. It stops short of explicitly naming hdphotohub_update_site as the alternative for modifying an existing site, so no explicit exclusion is stated.

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