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

Annotations cover the safety profile (readOnly, non-destructive, closed-world), and the description adds real behavioral context: it never substitutes a different city, it admits lack of coverage rather than guessing, it takes no personal data, and it mandates displaying the returned attribution. That is substantive disclosure beyond what the structured fields provide.

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 core behavior and example questions, then layers constraints (no city substitution, no personal data, attribution). Slightly diluted by promotional phrasing ('This is the whole product in one tool'), which is the only sentence not earning 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?

With no output schema, the description carries the return-value burden well: it explains the short concierge answer, the structured places, and the attribution field, and it warns that the tool may refuse when coverage is absent. An agent has everything needed to call and handle it correctly.

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 question, near, destination, and language are already documented in the schema. The description does not add syntax or format detail beyond noting the traveller's own words and multilingual input, so the baseline 3 is appropriate.

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+resource (ask a travel question, get a concierge answer grounded in Num's directory) and clarifies the return shape (answer plus named places as structured data). It is clearly distinguishable from siblings like search_places and place_details, which fetch data rather than answer questions.

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 when-not guidance — does not book, charge, or take personal details ('send none') — and sets the scope to the destination asked, never substituting another city. It stops short of routing the agent between this and sibling tools (e.g. use search_places for raw listings), so 4 rather than 5.

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