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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and closed-world scope, so the safety profile is covered. The description adds genuinely new behavioral context: it discloses the returned surface (public site key, allowed hostnames, options) and a security guarantee that 'Secrets are never listed,' which lets an agent reason about what data is safely retrievable.

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, both earning their place: the first defines the resource and its purpose, the second states what is returned and what is withheld. The key information (what a site is, what fields come back) is front-loaded with no filler.

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 a zero-parameter schema, full annotation coverage, and an existing output schema that documents return structure, the description needs only to establish purpose and contents, which it does. Minor gaps remain: no statement about ordering, completeness of the list, or account scoping, but nothing an agent needs to invoke it correctly 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 an unfiltered enumeration ('Shows each public site key, allowed hostnames and options') with no filtering or pagination arguments to explain, adding nothing misleading.

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 uses a specific verb+resource pair ('List BurrowGuard sites') and goes further by defining what a site is: 'the sign-up and contact forms protected against bots and bad addresses.' That domain gloss is what distinguishes it from create_burrowguard_site and update_burrowguard_site, though it never names those siblings explicitly.

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 implied rather than stated: an agent can infer it should call this to discover site keys before calling update_burrowguard_site or list_burrowguard_checks. There is no explicit when-to-use, no when-not-to-use, and no mention of alternatives such as list_burrowguard_checks, which shares the BurrowGuard prefix.

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