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

No annotations are provided, so the description carries the full burden, and it does: FREE, refreshed daily via eBay enrichment, merkle-committed on GradedPriceOracle, and crucially warns that these are eBay ASKS not sold prices and that asks are a ceiling. It also explains the frozen raw-card panel context, which is exactly the behavioral framing an agent needs to avoid misinterpreting the numbers.

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?

Front-loads the resource and its returned fields, then the provenance, then the trigger conditions. Dense but nearly every clause carries information. The em-dash parentheticals and oracle framing make it slightly heavier than needed for a single-param lookup.

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 no output schema and no annotations, the description fully supplies both: it enumerates returned fields and characterizes the value semantics (asks = ceiling) and the freshness/commitment guarantees. Nothing an agent needs to call this correctly is missing.

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 required param with 0% schema description coverage, so the description must compensate — and it does by defining product_id as the TCGplayer id obtained from search. That resolves the only ambiguity (where the id comes from). Slightly short of 5 because there is no note on expected id format beyond 'TCGplayer id'.

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 resource (graded slab asking prices for one card) with the exact breakdown returned (PSA/BGS/CGC medians by grade, listing counts, low/high, as-of date, price_basis). It is distinguishable from sibling market tools by explicitly framing itself as the graded-ask layer and naming the oracle it is committed on.

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?

Provides an explicit 'Use this when:' block with concrete phrasings ('what does a PSA 10 of this go for?', 'raw vs graded premium?') and routes the agent to the sibling loan_terms_preview before the free loan-terms quote. This is as close to when/when-not as you get.

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