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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=false). The description adds real domain behavior beyond that: a resource is single-location and shared across services, so booking a barber for one service closes the other. That cross-service coupling is useful context an agent cannot get from annotations. It does not describe return shape or pagination, but no output schema exists to cover it.

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?

Front-loaded with the core action ('List what can be booked') followed by the concept definition and the reuse instruction. The barber example is illustrative rather than padding since it explains the cross-service behavior, though it is slightly long for the value delivered.

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-parameter, read-only listing tool with no output schema, the description supplies what an agent needs: what a resource is and why to reuse existing ones. Nothing critical is missing, though a brief note on what fields come back would round it out.

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 there is nothing for the description to expand on; the baseline for 0 params is 4. No parameter semantics are missing or 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?

States a specific verb ('List') and resource ('what can be booked — staff, rooms, tables or assets'), and concretely enumerates the resource types. It is clearly distinguished from the sibling hub_create_booking_resource, so an agent can tell read-listing apart from creation without opening a 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?

'Read this before creating anything and reuse what is there' gives clear directional context — consult this before writing. However, it never explicitly names the alternative (hub_create_booking_resource) or states exclusions, so the routing is implied rather than spelled out.

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