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

With readOnlyHint, openWorldHint, idempotentHint and destructiveHint all provided, the safety profile is already covered. The description adds genuinely useful context: ranking originates from Vienna or the departure city, each result carries a why-it-matched reason, a Forecast vs Typical weather label, a price explicitly disclaimed as an estimate, and no personal data is involved.

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-loads the use case and packs real constraints into a dense paragraph. However, several sentences are presentation directives ('Show the weather as "forecast" or "typical"', 'do not repeat the weather source name') that dilute the operational content.

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 10-parameter, nested-object tool with no output schema, the description does the heavy lifting on result shape (city, country, why, weather label, estimate price, url, crew_url) and ranking behavior. It is close to complete; only sibling routing is 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 100%, so the schema already documents every parameter, including defaults, enums, ranges and patterns. The description largely restates this (dates or month, limit max 20, optional list), adding little beyond what the schema carries; baseline 3 applies.

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 precise verb+resource (destination search) and frames it as the TripHook Discover signed-out search, ranked from Vienna or a departure city. This distinguishes it from list_cities and search_public_hooks, so an agent can pick it 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?

Gives explicit trigger language ('any question like "where should I go" with a budget, a temperature, a mood, dates or a month') and states the dates-or-month requirement. It stops short of naming alternatives or when to prefer a sibling such as list_cities, so it is strong context without full routing.

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