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

Annotations already establish read-only behavior, and the description adds useful context that the catalog is 'live' and that the return values are valid converter slugs, with concrete examples. It does not disclose rate limits, pagination behavior, or authentication, but against the existing annotations the added return-shape detail is valuable.

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?

The description is a single front-loaded sentence with no wasted words. It puts the core action and return content first and uses examples efficiently.

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 the description needn't explain return values, and annotations cover read-only safety. However, for a search tool with two parameters and no schema descriptions, the missing parameter guidance leaves an agent without enough information to use search and limit 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 0%, so the description must compensate for undocumented parameters. It mentions searching the catalog but does not explain the 'search' parameter or the 'limit' parameter, its default of 50, or its maximum of 100; the slug examples offer only indirect help.

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?

The description states a specific verb and resource: 'Search the live JPG.now converter catalog and return valid converter slugs.' It distinguishes the tool from action-oriented siblings like convert_image_url and get_conversion_status by making clear this is catalog discovery, and it gives examples that concretize the output.

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?

The description implies the tool is used to discover converter slugs through search, but it never explicitly says when to use this versus alternatives such as convert_image_url. There are no exclusions or prerequisites stated, so the agent must infer the usage context.

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