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

No annotations are provided, so the description carries the full burden. It does disclose useful behavior: the return shape (low/typical/high, confidence), the data source (tracked marketplace data), and caching economics. It omits rate limits, auth requirements, freshness/staleness of cached data, and error behavior for unknown items.

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 tight sentences with zero waste, front-loaded with the core output shape and ending with the cost note. Every clause earns its place.

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?

There is no output schema, so the description correctly compensates by naming the return fields (low/typical/high, confidence) and the data provenance. Missing only usage routing against the three siblings, which is otherwise complete for a single-param lookup.

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?

One parameter ('q') at 100% schema description coverage with a concrete example, so the schema fully documents it. The description adds no format or constraint details beyond the schema; baseline 3 is appropriate when the schema does the work.

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: returns a second-hand price estimate (low/typical/high + confidence) for an item. The word 'Current' implicitly contrasts with the get_history sibling, but no sibling is named explicitly, so differentiation requires inference.

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 notes cached lookups are free, which is a mild cost consideration, but gives no when-to-use guidance and never mentions the alternatives (check_deal, get_history, get_sold). An agent must infer that this is the 'current price' tool versus the history or sold-data siblings.

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