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

With no annotations the description must carry the load, and it discloses the security-relevant traits: the link is public ("anyone with it can book"), the permission model (agent-initiated calls are refused; ask the user), and the return value (its URL). It omits idempotency, name-collision behavior, and any confirmation/rate-limit expectations.

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?

Four short sentences: purpose and URL, the usage constraint, the refusal fallback, and the return value. Nothing repeats the schema, and the most decision-relevant facts come first.

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 22-parameter tool with nested objects and no output schema, the description covers the two things the schema cannot: who may call it and what it returns. The dense per-parameter schema text carries the rest, so no critical gap remains, though a hint about which params are typical for a first link would have helped.

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 91% across 22 parameters, so the schema already explains slug, tz, ranges, hosts, reminders, etc. in detail. The description only lightly mirrors this ("in the hours given", the URL/handle/slug path), adding no new parameter meaning beyond what the schema states.

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 ("Make a public booking link") plus the resulting URL shape and what the link enables. It is clearly distinct from update_booking_link / delete_booking_link / list_booking_links by virtue of the verb, though it never names a sibling 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?

"Only when the user asked for one" is an explicit when-to-use constraint, and the refusal clause ("from an agent's own turn inside Caddie it's refused: ask the user") tells the agent what to do instead in that case. No alternative tool is named, so it falls short of a 5.

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