Katzilla MCP

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

Annotations already provide readOnlyHint=true, destructiveHint=false, idempotentHint=true, and openWorldHint=true, covering safety and idempotency. The description adds valuable context beyond annotations: it discloses the data source ('IPinfo'), update frequency ('updates daily'), and detailed return structure ('Katzilla envelope with quality scores and citation'), including audit features like SHA-256 hash. No contradiction with annotations.

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 efficiently structured in two sentences: the first states the purpose and source, and the second details the return format and audit features. Every sentence adds critical information without redundancy, making it front-loaded and appropriately sized for the tool's complexity.

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?

Given the tool's low complexity (one optional parameter), rich annotations covering safety and idempotency, and the presence of an output schema (implied by 'Has output schema: true'), the description is complete. It adds necessary context like data source, update frequency, and return structure, compensating adequately where structured fields might lack detail.

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?

The input schema has 100% description coverage, with the 'ip' parameter fully documented. The description does not add any parameter-specific details beyond what the schema provides, such as format examples or constraints. With high schema coverage, the baseline score of 3 is appropriate, as the description relies on the schema for parameter semantics.

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 clearly states the specific action ('Get geolocation data for an IP address'), resource ('using IPinfo'), and scope ('returns the Katzilla envelope'). It distinguishes from sibling tools by specifying its unique geolocation focus, unlike other geo tools like census-geocoder or nominatim that handle different geographic queries.

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 provides clear context for when to use this tool ('Get geolocation data for an IP address') and mentions the data source and update frequency. However, it does not explicitly state when not to use it or name alternatives among sibling tools, such as geo__geojs or geo__technik-news-ip, which might offer similar IP geolocation services.

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