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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds the single-vs-list response-shape distinction, which is useful, but it says nothing about the meaning of card_type, result volume, or ordering/pagination for the list case.

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 short sentence with no filler, and the more specific mode (card_id) is placed where it is easy to spot. It is terse to the point of under-specification, but nothing is wasted.

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?

With two undocumented parameters, no output schema, and no pagination or filtering context, the description is too thin for the tool's surface. An agent gets no guidance on what card_type does or what a list response looks like.

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 bears full responsibility for explaining parameters. It clarifies card_id (returns one card's details) but leaves card_type completely undefined — an agent cannot tell whether it filters by card type or selects a card variant.

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 indicates the resource (reloadable cards) and two retrieval modes: a list, or a single card's details when card_id is supplied. However, the verb is only implied by the name/title ('Get cards') and the phrasing 'Reloadable cards' is a noun fragment, so the purpose is inferable rather than stated outright. It does distinguish the list-vs-single behavior, which helps separate it from siblings like get_wallet or get_banking.

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: pass card_id for one card, omit it to get the collection. There is no explicit statement of when to use this tool versus get_wallet, get_banking, or list_recipients, and no prerequisites or exclusions are given.

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