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

With no annotations, the description carries the full burden and does well: it discloses that the want is held 'separate on the desk' on the AGENT PLANE until a second human request seconds it, that no requester identity is stored, and that queries are scrubbed before storage. Missing are return behavior and what happens if the library already holds the item.

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?

Key routing information (the kind/parameter mapping) is front-loaded in the first sentence, and the privacy/behavioral notes follow. It is dense but slightly ornate ('the same miss asked twice is one want asked twice'), which costs a little clarity for flavor.

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?

For a 4-parameter tool with 0% schema coverage, no annotations, and no output schema, the description covers purpose and part of the parameter mapping but leaves note undocumented and does not indicate what a successful call returns. Adequate to invoke, incomplete for confident use.

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 must compensate, and it partially does by mapping kind=missing→query and kind=expand→card_id, which is genuinely useful. But the fourth parameter, note, is never explained, and no value constraints are given for kind beyond the two named literals.

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 states a specific action (open a want) with two explicit modes disambiguated by parameter: 'kind=missing, give query' for acquisition vs 'kind=expand, give card_id' for expansion. This separates it functionally from siblings, though it never names want_offer or wants_list, so an agent must infer the routing from the semantics rather than from explicit contrast.

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?

It gives a real usage constraint ('Call this only when your principal genuinely needs what the keeping lacks') and a dedup rule ('the same miss asked twice is one want asked twice'). However, it never names the alternatives (want_offer, wants_list) or states when NOT to use this tool, leaving routing to inference.

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