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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds useful context that the catalog is 'live' and that results are slugs, but says nothing about pagination, ordering, whether search is substring or exact, or what happens when a search matches nothing — real behavioral gaps for a search endpoint.

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?

A single well-formed sentence that front-loads the action and catalog, then lists example output values. No filler; the example slugs earn their place by showing the expected return format, though one more clause on search behavior would have been worth the space.

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?

An output schema exists, so return values need no explanation, and annotations cover the safety profile. However, with two undocumented parameters and no guidance about how to page or search the catalog, the definition leaves the agent guessing on the mechanics of the call.

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 0% and neither of the two parameters (limit, search) is mentioned in the description. It never explains that limit caps results at 100 by default 50, nor how the search string is matched, so the description contributes essentially nothing beyond the bare 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?

A specific verb (search/list) plus a specific resource (XLS.now converter catalog) and the nature of the return value (valid converter slugs) with concrete examples such as xls-to-xlsx and xls-to-csv. It is clearly distinct from siblings like convert_image_url or get_conversion_status, though it never explicitly names them to differentiate.

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 only implied: an agent can infer this is a discovery/lookup step to find slug values before performing a conversion, but the description never states when to use it versus alternatives or that a slug from here is a prerequisite for other tools. No when-not-to-use guidance is given.

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