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

With no annotations, the description carries the disclosure burden and does well: it states the date range is inclusive and interpreted in the shop's time zone, documents a 500-job ceiling, and explains that a truncation indicator signals more matches existed. It does not explicitly state that the operation is read-only or describe the shape of the returned 'totals', which keeps 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?

Three tight sentences, each doing distinct work: scope and date semantics first, then sort options, then volume limits and truncation. No restatement of the name or filler content.

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 six-parameter report tool with an output schema present, the description covers what the schema cannot: range interpretation, ordering intent, and result-set limits. The remaining gap is the sibling relationship with costs_job and the ambiguity of whether margin sorts ascending or descending.

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 coverage is only 50%, so the description's contribution matters: it adds the inclusive/time-zone semantics for from/to and the 'lowest first' ordering for the profit sort, plus the practical cap that limit cannot exceed 500. It says nothing about shop_id or about how margin and date sorts order, leaving part of the enum behavior underspecified.

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 gives a specific verb-and-resource pairing: it produces job costing totals across a date range of jobs, which is clearly a report/list operation rather than a mutation. The plural 'across jobs' implicitly distinguishes it from the singular sibling costs_job, but it never names that sibling, so the differentiation is left to inference.

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?

Usage is implied rather than stated: the range semantics and the 'to find the losers' framing convey a profitability-review use case. However, there is no explicit when-to-use guidance, no prerequisites, and no mention of when the agent should prefer the sibling costs_job for a single job's costing instead.

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