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

Annotations already cover the safety profile (readOnlyHint, openWorldHint false, destructiveHint false), so the description's job is to add outcome detail — and it does: a hard cap of 12 results, the exact fields returned, and the fallback to clarifying questions when no criteria are supplied. No pagination or ranking behavior is disclosed, which keeps it from a 5.

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?

Two compact sentences, front-loaded with the core action and searchable facets, then the return shape and the no-query fallback. Every clause carries information an agent needs; nothing is padding.

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 an output schema present, the description needn't detail return values, yet it summarizes them usefully and adds the 12-result cap and empty-query behavior. For a 9-optional-param search tool this is nearly complete; only the tone/art_style facets are left entirely to the schema.

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 56%, and the description only re-lists facet names (occasion, recipient, name, age, interests, city) without adding semantics beyond what the schema already says — e.g. the 'unknown values return the nearest valid ones' behavior lives in the schema, not here. Two enum params (tone, art_style) go unmentioned, so the description doesn't fully compensate for the coverage gap.

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 verb+resource ('Searches ModCard's greeting cards') and enumerates the searchable facets, then names what comes back (up to 12 cards with id/title/picture). The parenthetical tying the returned id to choose_card's card_id distinguishes it from the sibling that consumes its output.

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?

Explicitly covers the zero-parameter mode ('with nothing to search on, the questions that make a card personal'), which is a real usage branch an agent must know about. It stops short of naming when to prefer this over siblings like list_my_orders or order_card, so no exclusions are stated.

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