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

Annotations already declare the tool as read-only, idempotent, and non-destructive. The description adds context about the output fields and default sorting behavior, which is useful. It does not contradict 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 two sentences, front-loads the purpose, and provides a high-level usage tip without unnecessary detail. Every sentence adds value.

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 straightforward read-only search nature, the description covers the essential aspects: what it searches, what it returns, and how to retrieve all results. The schema handles parameter details, and sibling tool names clarify the domain. The absence of an output schema is mitigated by the description listing key output fields.

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 schema provides 100% coverage for all six parameters with detailed descriptions. The description adds a practical hint about the no-filters call and the relationship between sort options and output fields, enhancing the schema's baseline information.

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 function: to search and compare credit cards in Poland. It specifies return values such as fees, RRSO, grace period, rewards, and moneyback, which distinguishes it from sibling search tools for other financial products.

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 gives clear context for when to use the tool (when searching/comparing credit cards) and explicitly mentions that calling with no filters returns all cards sorted by score. However, it does not explicitly discuss alternatives or when not to use it, though sibling tool names suggest the distinction.

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