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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered by structured data. The description adds real behavioral context beyond that: results are filtered to executable liquidity because unfunded offers are removed, which changes how the output must be interpreted. It stops short of describing pagination or empty-side behavior, so not a 5.

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-loaded with the core definition, then clearly delimited 'When to use', 'Prefer another tool' and 'Example' sections. The embedded example largely duplicates the schema's own example, a minor redundancy in an otherwise tight definition.

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?

For a read-only pair lookup with an output schema and 100% parameter coverage, what the tool does, when to use it and which siblings to prefer are all present. Remaining details (defaults for depth, behavior when one side is empty) are adequately handled by the schema/output schema.

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%, so base, quote and depth are already fully documented, including the depth rounding rule, in the schema itself. The description's example repeats the base/quote format already shown in the schema and adds no new meaning. Baseline 3 applies when the schema does the heavy lifting.

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 ('CLOB order book for a currency pair') and a distinguishing qualifier ('with unfunded offers removed'). An agent can separate this from xrpl_amm and xrpl_slippage without opening any schema.

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 'When to use' line plus two named exclusions routing to sibling tools (AMM liquidity -> amm page, cost estimate -> slippage page). The condition that selects each alternative is stated, not implied.

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