Get decks of cards

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

Annotations already declare readOnly, idempotent, and non-destructive behavior, so the safety profile needs no restating. The description does add the useful fact that the result is an object keyed by deck name whose values are the matching card IDs, which matters because there is no output schema. It says nothing about how cards in multiple decks or unknown card IDs are handled.

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?

One sentence containing the input constraint, the operation, and the return shape, with nothing extraneous. The closing clause 'the given card IDs that are in it' is slightly tangled, which keeps it from a perfect score.

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?

A one-parameter read tool with full schema coverage and no output schema, and the description covers both the disambiguation (card vs note IDs) and the shape of the response. It is close to complete, missing only edge-case behavior for nonexistent or multi-deck cards.

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 coverage is 100% and the single parameter already documents 'card IDs, not note IDs; get them from find_cards or notes_info.' The description repeats the card-vs-note distinction without adding format, ordering, or size-limit detail beyond the schema, so the baseline 3 applies.

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?

States a specific operation: given card IDs, return a mapping of deck name to the card IDs contained in each. This clearly distinguishes it from siblings like deck_names (lists name/ID pairs) or find_cards (searches cards). It does not explicitly name a sibling, keeping it just below a 5.

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 implied — supply card IDs, learn which decks own them — and the 'not note IDs' parenthetical warns against a common input mistake. However, there is no explicit when-to-use or when-not-to-use guidance relative to alternatives such as cards_info or change_deck.

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