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

Annotations already declare readOnly, non-destructive, closed-world; the description adds useful context beyond them: it exports the 'current saved lines' (snapshot semantics) and names a prerequisite feature. It does not say how the download is delivered (URL, stream, attachment) or what happens with no saved lines, which is the main remaining gap.

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 sentences, front-loaded with what is produced, then filters and the prerequisite. Little waste; only 'Fills and Supplier lines' jargon is unexplained.

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 does say the return is a two-section workbook, which is the most important return detail. But for a five-filter export tool it omits filter interaction semantics and delivery mechanism, leaving meaningful gaps.

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%, so the description must compensate. It maps to all five fields at a high level (batch, client, invoice dates, approved slips) and clarifies the dates are invoice dates, but gives no format hints (UUIDs, date types, whether the range is inclusive or AND-combined). Partial compensation, not full.

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 (export/download) and resource (fuel-slip Fills and Supplier lines workbook), and identifies the exact artifact produced, which separates it from generic invoice exports in the sibling list. It doesn't explicitly name a sibling alternative, but the resource is distinctive enough that confusion is unlikely.

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?

Gives a real prerequisite ('Requires the workspace fuel-slip feature') and describes optional filtering, which implies when to use it. However there is no explicit guidance on when to prefer this export over e.g. export_client_invoices or export_vendor_statement_workbook, and no exclusions.

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