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

Annotations already declare the safety profile (destructive=false, openWorld=true, idempotent=false), so the bar is lower. The description adds genuinely new context the annotations do not carry: the cost model ('0.05 USDC on Base per report') and the boundary conditions (no FX, no tax inference, no supplier verification), which an agent needs before invoking a paid operation.

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?

Three short sentences, fully front-loaded: capability first, boundary conditions second, cost last. Every sentence carries distinct information with no restatement of name or title.

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, the description must carry return-value burden; it says rankings and ties are reported but does not describe the response shape, ordering guarantee, or how ties are represented. For a paid, no-output-schema tool the coverage is adequate but leaves the agent guessing about the result format.

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% and there are three required nested parameters (currency, requirements, quotes) that are entirely undocumented. The description offers only indirect hints — 'same complete order' and 'shipping' gesture at the requirements/quotes relationship — but never explains currency-matching rules, quantity semantics, or decimal-string formats.

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 and resource ('rank supplier quotes'), the scope ('for the same complete order'), and the method ('exact decimal arithmetic and shipping'). Siblings (demo, ping, service_info) are unrelated utilities, so no further differentiation is needed — an agent can identify this instantly.

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?

Explicit exclusions are given: incomplete quotes are dropped, and no FX, tax inference or supplier verification is performed, which tells the agent when this tool is inapplicable. It does not name an alternative tool or state prerequisites (e.g. quotes must share the order's currency), so it falls short of a full 5.

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