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

With no annotations, the description carries the burden and does disclose the key data condition (only cities with published weekends), the field set returned, and that results are 'Paged.' It omits any note on result ordering or that the default status filter is 'published', though the schema covers the latter.

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 tight sentences front-load the core purpose, then the discovery value, then paging. Every clause earns its place, though 'Paged.' as a fragment and the dense season-factor gloss slightly compress readability.

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?

No output schema exists, yet the description enumerates return fields and explains the season-factor scale, which is exactly what an agent cannot get from structured data. Paging is flagged; only result ordering and the interaction of the status filter with 'published weekends' are left unstated.

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 lang, limit, offset and status are already fully documented; the description adds nothing about them. Its one semantic addition ('1.0 = shoulder season; higher is dearer') explains a returned value, not a parameter, so 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?

Specific verb ('List') plus a precisely scoped resource ('cities that have published weekends') and an enumeration of the returned fields (slug, IATA, currency, twelve season factors). It is clearly separable from the sibling get_city, which fetches one city rather than listing discoverable slugs.

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?

'Start here to discover city slugs for every other tool' gives an explicit entry-point role, implying get_city and the itinerary/fare tools are the follow-ups. It stops short of naming any tool to avoid or a when-not-to-use condition, so it is clear but not fully routing.

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