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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful behavior: results are computed server-side from live Fortnox data and cover all pages, so the agent knows the output is complete rather than a partial page.

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?

The core scope is front-loaded in the first clause, followed by illustrative questions and a short provenance note. It is compact, though the bilingual Swedish/English mix makes it slightly less crisp than it could be.

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 an output schema present and annotations covering safety, the description only needs to establish scope, and it does: both customer and supplier invoices, overdue plus upcoming, per invoice, full dataset. It could still say how it differs from the aging reports, but nothing essential is missing for correct invocation.

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 every one of the four parameters (date, part, sida, dagar) is already documented in the schema. The description only obliquely echoes the default 30-day window through its example question and adds no format or edge-case detail 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 a specific verb and resource: it lists customer and supplier invoices by due date, covering both overdue items and those falling due in the coming days, at invoice level. That is clearly distinguishable from siblings like get_payables_aging or get_receivables_aging, though the description never names an alternative explicitly.

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 two example questions ("Vad förfaller de närmaste 30 dagarna?", "Vilka leverantörsfakturor ska betalas nästa vecka?") imply the right usage context well. However, there is no explicit statement of when to prefer this over the aging-report siblings or the plain invoice list tools, so routing still requires inference.

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