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

Annotations only say read-only/idempotent/closed-world; the description goes well beyond them by defining each availability reason ('scope', 'seat', 'disabled', 'plan'), noting that a viewer seat is read-only regardless of grant, that an API key is read-only by design, and that only the caller's own grant and account are described. This is exactly the context an agent needs to interpret the response and avoid pointless retries.

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?

It is front-loaded with the purpose, and nearly every clause carries real information, but the body is a single run-on sentence with nested parentheticals defining four failure reasons — accurate yet hard to parse at a glance. Splitting the availability reasons into a short list would keep the content while greatly improving scanability.

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?

There is no output schema, so the description must carry the return contract, and it does: every field is named and the enumerated reason values are defined. For a zero-parameter diagnostic tool, nothing an agent needs in order to call it or interpret its result is missing.

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?

There are zero parameters, so the baseline is 4; the description correctly implies a no-argument, caller-scoped call ('Only the caller's own grant and account are described'), which adds a small amount of meaning about implicit scoping.

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 opening clause states the exact resource and scope: 'What this connection can do right now', then enumerates the concrete fields returned (credential, plan, seat, scopes, siteAccess, per-tool availability). An agent can distinguish this diagnostic tool from siblings like get_usage or current_site 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?

Usage is only implied: the description explains what the availability flags mean, which suggests it is a pre-flight check before calling other tools, but it never states that explicitly, nor does it name a sibling alternative or an exclusion. The heavy explanation of failure reasons effectively does the routing work, so this is more than nothing but short of explicit guidance.

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