What this service can do

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

Annotations already declare this a safe, idempotent, non-destructive read, so the safety bar is met. The description adds real behavioral value beyond that by disclosing the exact availability vocabulary returned and the 'honest availability label' semantics, which tells the agent how to interpret results rather than just that the call is safe.

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 sentences with no filler: purpose first, then filters, then the fallback route, then an example. The availability enumeration is slightly list-heavy but is load-bearing information, not padding.

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 correctly fills the gap by describing what a result contains (availability label, category, usage guidance). Combined with the routing hint to request_capability, an agent has enough to call this correctly; only the filter value semantics are thin.

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 0% across four optional params, so the description must carry the load. It names all four filters (query, category, availability, tag) and the example pins down query and availability usage, but category and tag semantics and any value constraints remain unexplained, so compensation is only partial.

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 ('List what this service can and cannot do today') and immediately enumerates the availability taxonomy it returns. It also differentiates itself from the routing sibling by naming request_capability for the missing case, so an agent can tell what this tool is versus a directory or help search.

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?

Gives explicit filtering options and a concrete example, plus a clear handoff rule: 'If what you need is missing, call request_capability.' It does not, however, distinguish itself from other read-style siblings such as find_help or search_directory, so the when-not-to-use case is only partially covered.

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