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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered and this is clearly a pure computation. The description adds the fee-stack ordering (delivery, then transaction fee, then pickup fee) and the pickup_fee_waived rule, which is useful context, but says nothing about permissions, side effects, or response shape.

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?

Usage is front-loaded, but the body is dense with nested clauses and repeats itself (Facebook Marketplace/Craigslist/OfferUp appear twice, and the take-home framing is restated in the closing two sentences). It is parseable but clearly longer and harder to follow than the underlying four parameters warrant.

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 carries the burden of describing return values; it hints at pickup_fee_waived and the payout figure but never enumerates the response fields. It also defers essential fee terms to 'the server instructions', which the agent may not have, leaving the quote semantics partly incomplete.

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 100%, so the baseline is 3, but the description adds real semantics beyond the schema: it defines the mutual-exclusion rule ('give exactly one of') and clarifies how each input differs (price_usd = pre-Sept-4-2026 asking price, buyer_sees_usd = a price a buyer pays, desired_payout_usd = target take-home). The schema enforces none of that exclusivity, so this is genuine added value.

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 tool computes a seller's take-home/payout math for a category, and the description spells out the three input modes (desired_payout_usd, buyer_sees_usd, price_usd), which is a fairly specific verb+resource. It never names the adjacent pricing tools (pricing_quote_crosslist, pricing_get_guide), so the agent must infer the boundary from the mode list rather than an explicit distinction.

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 opening sentence gives a concrete when-to-use trigger (selling a large/valuable item, including crosslisting to Facebook Marketplace/Craigslist/OfferUp), and it later imposes the 'give exactly one of' rule. It offers no explicit when-not condition or named alternative among sibling pricing tools.

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