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 this: it discloses the data source (UN Comtrade), update frequency (daily), return format (Katzilla envelope with data, quality, citation), and details like quality metrics and citation components (source URL, license, SHA-256 hash). This enriches behavioral understanding without contradicting 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 highly concise and front-loaded, with two sentences that efficiently convey the tool's purpose, source, update frequency, and return structure. Every sentence adds critical information without redundancy, making it easy for an agent to parse and understand the tool's functionality quickly.

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 complexity (5 parameters, 100% schema coverage, annotations, and an output schema), the description is complete enough. It covers the data source, update behavior, and return format in detail. With annotations handling safety and idempotency, and the output schema presumably defining the Katzilla envelope structure, no significant gaps remain for agent understanding.

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%, with each parameter well-documented in the schema (e.g., defaults like '842 = USA', '0 = World', 'M = imports'). The description does not add any parameter-specific semantics beyond what the schema provides, such as explaining trade flow codes or commodity codes in more detail. However, the baseline is 3 since the schema adequately covers parameter meanings.

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 tool's purpose with a specific verb ('Query') and resource ('international trade data from the United Nations Comtrade database'). It distinguishes itself from siblings by specifying the exact data source (UN Comtrade) and domain (international trade), unlike other economic tools like economic__bea-gdp or economic__bls-series that focus on different economic indicators.

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 usage context by mentioning the data source and update frequency ('updates daily'), but does not explicitly state when to use this tool versus alternatives. It lacks guidance on prerequisites, exclusions, or comparisons to sibling tools like economic__wto-trade or trade__eurostat-trade, leaving the agent to infer usage from the domain.

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