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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds genuinely useful behavioral context beyond that: the returned fields (unit price, cost, quantity, amount) and critically that monetary values are in cents, which prevents unit misinterpretation. Pagination behavior is not mentioned, keeping it short of 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?

Two tight sentences with no filler; the core purpose and the returned fields are front-loaded, and the API endpoint reference is compact. Every clause earns its place.

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?

No output schema exists, so the description must describe returns, and it does list the meaningful fields plus the cents denomination. For a simple one-parameter read-only list tool this is nearly complete, with only pagination behavior left unspecified.

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 there is only one required parameter (job_id), so the schema already documents the input fully. The description implies a job target but adds no syntax or format details beyond what the schema provides, matching the baseline 3.

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 (List) and resource (line items on one job), and enumerates the kinds of items (services, materials, labor, discounts), which distinguishes it from siblings like housecall_list_job_invoices. An agent can identify the tool's function without opening the 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?

The scoping phrase 'on one job' implies usage context, but there is no explicit when-to-use guidance, no exclusions, and no named alternative (e.g., list_job_invoices for invoice-level data). Usage is only implied.

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