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

No annotations are provided, so the description carries the full burden, yet it discloses nothing about assumptions: rounding, whether optional params like vip/graded change fee tiers, whether unsupported parameter combinations silently ignore inputs, or which marketplace-specific fields are conditionally required (e.g. comcService for comc). Only the broad 'fees and net profit' outcome is stated.

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?

It is a single front-loaded phrase with no padding, so nothing is wasted, but the terseness reflects under-specification rather than discipline. There is no structure beyond one noun phrase.

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 10 parameters, no annotations, and no output schema, the description should explain the fee model, conditional requirements, and the shape of the result. A single sentence cannot carry that, so an agent must guess at critical details before calling.

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 description mentions no parameters at all, while schema coverage is only 60% and several params (vip, graded, comcService) have no schema description or obvious semantics. For a 10-parameter calculation tool this leaves meaningful ambiguity, such as what 'vip' or 'graded' change in the fee formula.

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 phrase names a specific output set (all marketplace fees plus net profit) scoped to a single card sale, which is more informative than restating the name. It never mentions the sibling tools best_place or evaluate_flip, so an agent cannot tell from the description alone how it differs from evaluate_flip's apparent profit calculation.

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?

There is no when-to-use guidance, no prerequisites, and no reference to alternatives, despite two sibling tools that plausibly overlap on profit math. The agent is left to infer that this is the detailed per-marketplace fee breakdown versus the flip evaluation.

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