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

Annotations already declare readOnly/idempotent/non-destructive, and the final sentence ('Läser bara, ändrar inget') merely restates that. However, the description adds behavior annotations cannot express: sort order, one-page-at-a-time pagination, and the full return shape (totals, limit/offset, and per-voucher fields including sign convention for öre). That is real added context, though no auth or rate-limit notes.

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?

Single dense paragraph, front-loaded with purpose, then alternatives, then return values. Every clause is useful except 'Läser bara, ändrar inget', which duplicates the readOnly annotation and could be dropped; the long return-field enumeration is justified because no output schema exists.

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 carries the return-shape burden and does so completely: totals, pagination fields, and per-voucher payload including amount sign convention. Combined with sibling routing and sort/pagination behavior, an agent has everything needed to call and interpret this list tool.

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 parameter (year, month, limit, offset, orgnr) is already documented in the schema. The description restates limit/offset only implicitly via 'en sida i taget' and 'totalt antal, limit och offset', adding no syntax or format detail beyond the schema. Baseline 3 applies.

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 ('Listar bokförda verifikat') plus fiscal-year scope, sort order ('sorterade på serie och nummer') and pagination ('en sida i taget'). It also explicitly distinguishes itself from get_voucher and get_general_ledger, so an agent can tell it apart from siblings without opening a 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?

Gives explicit usage ('Använd för att bläddra bland verifikat eller hitta ett id') and names two alternatives with the conditions that select each ('för ett enskilt verifikat med momskoder, använd get_voucher'; 'för ett kontos rörelser, get_general_ledger'). No routing decision is left to inference.

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