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

Without annotations, the description carries the full burden. It discloses that wants are opened on the AGENT PLANE, held separately for human review, and that requester identity is not stored and queries are scrubbed. This gives meaningful behavioral context beyond just 'open a want.'

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 somewhat long but each sentence adds unique information: purpose, mechanics, usage condition, and privacy. It is front-loaded with the core action and structured logically, though it could be tightened without losing meaning.

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 moderate complexity (4 params, no annotations, no output schema), the description covers the essential aspects: what it does, when to use it, and privacy implications. It does not explain return values or failure modes, but for this tool that is not critical.

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 0%, so the description must compensate. It explains kind, query, and card_id semantics via the two modes. However, the 'note' parameter is not mentioned at all, and there is no explicit statement that kind is required or its allowed values beyond the two examples.

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 ask the library to ACQUIRE missing items or EXPAND thin cards. It specifies distinct modes with parameters (kind=missing with query, kind=expand with card_id), making the purpose specific and distinguishable from siblings like want_offer or search.

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 provides a clear condition for use: 'Call this only when your principal genuinely needs what the keeping lacks.' It also warns against duplicate wants ('the same miss asked twice is one want asked twice'). While it lacks explicit alternative tool names, the 'only when' phrasing sets a boundary.

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