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

Goes well beyond the annotations, which only declare readOnlyHint=false and openWorldHint=true. The description discloses the double opt-in mechanism (an email to the user's own address, their click confirms it), that no account is created and nothing is charged, and that a human specialist replies by email — all material side-effect and privacy context for a non-read-only tool.

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 front-loaded sentences: behavior and confirmation flow first, then cost/consent guarantees, then the accepted inputs. No filler, though the final sentence is a partial restatement of the schema.

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 an 8-parameter, no-output-schema side-effect tool, the description covers the flow, cost, consent, and input expectations well. It is slightly thin on what the caller gets back after the request is sent (e.g. a confirmation response), but nothing critical for correct invocation 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?

Schema description coverage is 88%, so the schema already documents email, what, when, budget, from_city, travelers and sailing_ids. The description adds only a loose summary of the same fields and their optionality, and omits `name` entirely, so it does not meaningfully exceed the schema.

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 action (send a help request email to a Fantasize cruise specialist) and a specific resource (trip planning request), which is clearly distinct from sibling search/info tools like search_cruises and get_cruise. An agent can tell this is a lead-handoff tool, not a data-retrieval one.

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: the description explains the confirmation flow and that it's free, which hints at when a user would want it, but it never says when to pick this over search_cruises, compare_cruise_lines, or cruise_options. No exclusions or prerequisites (e.g. 'use only after the user has looked at sailings') are given.

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