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

Goes well beyond the annotations: it discloses the required READ:FINANCE scope, that end is exclusive, that amounts are in the smallest currency unit and may be negative, the returned fields (timestamp, amount, type, originating transaction UUID) and offset-based pagination via next_offset. That is exactly the extra context annotations cannot carry.

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?

One dense but front-loaded sentence plus short permission, pagination and endpoint notes; the resource and date window lead. The telegraphic style ('Page with next_offset') is efficient but occasionally terse enough to read as shorthand.

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 a full schema, read-only annotations and no output schema, the description still enumerates the response fields and pagination mechanism, and flags the auth requirement. Nothing material for a correct call is missing.

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 100% and already documents ranges, defaults and the offset/next_offset pairing, so the description only needs to reinforce. It does add the semantic edge that end is exclusive and that the returned records are paginated, but most parameter detail duplicates the schema.

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 (list transactions), names the exact transaction categories covered (payments, fees, payouts, adjustments), the accounts (LIQUID/PRELIMINARY) and the date window. This is clearly distinguishable from siblings like zettle_get_account_balance or zettle_list_purchases.

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 mention of READ:FINANCE scope and the endpoint signal a finance-reporting context, but it never says when to choose this over zettle_get_account_balance or zettle_get_payout_info, nor any when-not condition.

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