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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered structurally. The description adds the shape of the payload (description, timezone, booking link, services with ids/duration/price), but says nothing about auth requirements, rate limits, or error behavior for an unknown slug. With annotations carrying the safety burden, a 3 is appropriate.

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?

One dense sentence with zero waste; the resource and its input source are front-loaded, and the downstream id dependency is attached at the end where it matters. Every clause earns its place.

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?

An output schema exists, so return values need not be re-explained, yet the description still flags the one field that matters for chaining (service ids). Combined with the slug provenance, the agent has everything needed to call this tool correctly and use its result.

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%, so the single slug parameter is undocumented in the schema. The description compensates by stating its provenance ('from search_kaio_businesses'), which tells the agent where to obtain a valid value. It does not give format details, but the provenance is the operationally important part.

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 (retrieve) and resource (a Kaio business) and immediately enumerates the returned fields, so the agent knows exactly what it gets. It also names the sibling that produces the input (search_kaio_businesses), making it distinguishable from the other three tools 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?

Clear contextual guidance: the slug comes from search_kaio_businesses, and the service ids it returns are what kaio_free_slots and booking need, which tells the agent where this sits in the call chain. It lacks an explicit when-not statement (e.g., don't call it if you already have ids), so it falls just short of 5.

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