market_for_sale_packages

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

With no annotations, the description carries the full burden of behavioral disclosure, and it does so well. It explicitly discloses that oversized packages are refused without dropping cards, that it makes a single GET request without auto-paginating, and that arrays are limited to 100 rows and 256 KiB with truncation reported. This goes beyond a simple read operation and gives the agent essential operational constraints.

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 moderately long but every sentence adds distinct value: purpose, integrity guarantees, request behavior, filter caveat, and response limits. It is well-structured and front-loaded with the core purpose. No redundant or filler sentences are present, earning a strong conciseness 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?

Given that the tool takes no parameters and there is no output schema, the description covers the critical behavioral context: completeness guarantees, pagination behavior, size limits, and truncation reporting. It does not describe error codes or response format, but for a parameterless read tool, the provided information is sufficient for an agent to call it correctly.

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?

The input schema is empty, so there are no parameters to document. However, the description confusingly references 'Required inputs' and 'declared filters' despite the schema having none. This contradicts the schema and adds no meaningful parameter information. Since schema coverage is technically 100% (vacuously), the baseline is 3, but the misleading mention of required inputs lowers the score.

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 reads listed card packages and preserves their card sets intact. It specifies the resource ('card packages') and the action ('read'), and the mention of 'retaining each package's cards intact' differentiates it from grouped market tools that may aggregate or split data. It is unambiguous about what it returns.

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 does not explicitly state when to use this tool over alternatives like market_for_sale_grouped or market_query_by_card. It mentions 'Required inputs reflect tool policy' but provides no concrete guidance on selection criteria or exclusions. The lack of a clear 'use this for X, not Y' reduces its usefulness for an agent deciding between siblings.

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