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

Annotations already declare destructiveHint=true, idempotentHint=true and readOnlyHint=false, so the safety profile is covered. The description adds value the annotations cannot: that the reversal posting is performed by the code itself when the invoice was already booked, plus the required auth scope (book). That is meaningful side-effect and permission disclosure.

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 short, front-loaded clauses; the core action leads and the prerequisite trails. The 'KODEN postar återföringen' emphasis is a little cryptic in phrasing but carries real information, so there is little waste.

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 2-parameter mutation tool with no output schema and full annotation coverage, the description supplies the pieces an agent still needs: the reversal semantics, the auth scope, and the argument set. Return values need not be described. Minor gap: it does not clarify preconditions such as payment status.

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 50% – orgnr is well documented in the schema, but invoice_id has no description anywhere. The description merely restates the argument names ('Argument: orgnr, invoice_id') and adds no format, range, or lookup guidance, so it fails to compensate for the undocumented invoice_id.

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 ('Makulera en leverantörsfaktura') and immediately scopes the behavior to reversing an existing booking, which cleanly separates it from sibling cancel_customer_invoice and the various reverse_* tools. It does not name a sibling explicitly, so it stops short of a 5.

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 conditional trigger ('återför bokföringen om den redan bokförts') and a hard prerequisite ('Kräver scope book'), which is real usage context. However, it never says when to prefer this over alternatives such as reverse_supplier_payment or reverse_voucher, so the routing guidance is only implied.

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