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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds real behavioral context beyond that: grade columns vary by set, with vintage sets potentially carrying different grade tiers than modern ones — a non-obvious output-shape detail. No rate-limit or auth notes, but none are implied.

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 sentences, front-loaded with the return payload before the parameter-sourcing guidance. The parenthetical on grade tiers earns its place by preempting confusion. Slightly dense but no filler.

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?

An output schema exists, so return values need not be described, and read-only/open-world annotations cover the safety profile. Parameter sourcing and the varying-grade behavior are addressed; only identifier format details remain unstated.

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 description coverage is 0%, so the description must carry the burden, and it does: it explains that category_path, set_path and set_id together identify the set and where each value can be obtained. It does not clarify the format/syntax of each identifier (e.g. whether set_path is a slug or URL segment), leaving a minor gap.

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 ('One PSA Price Guide set's full grade-by-grade price table') and immediately clarifies scope ('every card in the set with PSA's own formatted price per grade column'). It names the sibling tools (psa_price_guide_search, psa_price_guide_categories) it depends on, so an agent can place it in the workflow without opening schemas.

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?

Explicitly tells the agent how to source each parameter (fields from a psa_price_guide_search result, or category_path from psa_price_guide_categories combined with a browsed set_path/set_id), which is strong actionable context. It stops short of stating when NOT to use this tool versus the search/categories siblings, so it lacks an explicit exclusion.

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