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

Annotations already declare readOnlyHint=true, so the safe-read profile is covered. The description adds useful behavioral context by disclosing the returned line-item fields and the underlying GET endpoint, though it omits pagination behavior and authorization requirements.

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 tightly written sentences with zero filler. The core purpose and returned contents are front-loaded, and the endpoint reference is supplementary rather than padding.

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 list tool without an output schema, the description supplies the essential purpose, scope, and return contents while annotations cover safety and the schema covers pagination and include options. The only minor gap is that pagination behavior and association embedding could be explicitly acknowledged, but the schema sufficiently compensates.

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 the schema already documents page, per_page, include, and opportunity_id. The description repeats the opportunity_id concept in the endpoint but adds no parameter-level syntax, defaults, or embedding semantics beyond what the schema provides.

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 the specific verb 'List' and the exact resource 'line items on one opportunity', then enumerates the contained fields (products, services, groups, quantity, rate, discount, dates, charge totals). No sibling tool lists opportunity line items, so an agent can distinguish it immediately from get_opportunity or list_opportunities.

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?

The description gives clear context—one opportunity, line-item contents—which implies usage when an agent needs those details. However, it never states when to use this tool versus get_opportunity or list_opportunities, and offers no exclusions or prerequisites beyond the required opportunity_id.

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