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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safe-read profile is covered. The description adds what is returned (plan, limits, owned-site count), but says nothing about auth requirements, quota semantics, or the token's optionality beyond what the schema already states.

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?

One efficient sentence with the payload front-loaded and no filler. Slight redundancy between 'limits' and 'how many sites your token owns', but overall tight.

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 zero-required-param read-only tool with annotations covering safety and no output schema, the description states what the caller gets back. It is essentially complete; only auth/quota nuance is left implicit.

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% for the single optional 'token' parameter, so the schema fully documents it (format, optionality, Authorization fallback). The description adds no parameter-level detail, which is the correct baseline when the schema does the heavy lifting.

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 ('read') and resource ('your plan, limits, and how many sites your token owns'), which is an account/identity read clearly distinct from the site-scoped siblings (get_site, list_sites, publish_site). It doesn't explicitly name a sibling to route away from, but the resource itself separates it from all six.

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?

'Use this to read...' implies intent but gives no when-not guidance or alternatives (e.g., the difference from list_sites when checking site ownership). Usage is inferable from the resource, not spelled out.

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