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

Annotations already cover the safety profile (readOnlyHint, destructiveHint=false, openWorldHint=false), so the description adds real value on top: it discloses that kake_ratio is computed as 1 - discount, that Over-MSRP and Catalog-Off rows are kept in separate columns and excluded from kake_ratio, and that rates are ceilings with list bases varying by row. These are substantive semantic caveats not present in the annotations.

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 core purpose is front-loaded and the example is useful, but the entire text is duplicated in Japanese and English, roughly doubling length without adding information. Several caveats are packed into dense clauses that would be clearer as separate sentences.

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-format explanation is not required. The description adequately covers data provenance (specific contract IDs), the computed kake_ratio, and the ceiling/list-base caveats, giving an agent enough to interpret results correctly; only explicit alternative-tool routing 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?

Schema description coverage is 100% and all seven parameters carry bilingual schema descriptions, so the baseline is 3. The description adds an example query value and clarifies that the returned 'rate' is a ceiling, but it does not add per-parameter meaning beyond what the schema already provides for basis, vendor, source_id, limit, or offset.

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 states a specific verb and resource — returns published discount rates off list price from U.S. public contracts — and enumerates the exact contract sources (Washington DES 23623 plumbing, 11121 electrical, NASPO ValuePoint MRO) plus named vendors. It is clearly distinguishable from pricing siblings like get_price_range or get_fair_price_sources, though it never explicitly contrasts itself with them.

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?

An example query ('eaton breakers') and the enumerated sources imply when the tool is useful, but there is no explicit when-to-use statement, no conditions for choosing this over get_us_construction_prices or get_fair_price_sources, and no stated exclusions. Usage is only inferable.

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