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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and closed-world, so the safety profile is covered elsewhere. The description adds genuinely useful context beyond that: it explains the tool reports the *reason* when the service is not selling, and that this reflects configuration state rather than process liveness.

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 sentences, front-loaded with the primary answer, with the second sentence doing real work by disambiguating against the health endpoint. No filler and nothing that needs to be read twice.

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?

With no output schema, the description must carry the return-value burden, and it does reasonably well by enumerating what is reported (selling state, mode, network, failure reason). It could be slightly more explicit about the shape of the response, but for a zero-param read tool this is close to complete.

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 tool takes zero parameters, so the baseline is 4 and there is nothing for the description to disambiguate. The description correctly implies a no-argument status read.

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?

The description states a concrete read of a specific resource state: whether the service is selling now, in which mode, on which network, and why not if it isn't. It also explicitly separates this resource from the liveness endpoint at /health. It does not differentiate from the sibling tools (get_docs, get_pricing, lookup_site), though those are in unrelated domains.

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?

"This is configuration, not liveness: the health endpoint is at /health" gives clear routing guidance, telling the agent when to use this tool versus the health endpoint. It stops short of naming an actual sibling tool or stating conditions such as caching or refresh behavior.

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