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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds real value beyond that with the required auth scope (READ:FINANCE) and the underlying endpoint GET /v2/payout-info. It says nothing about freshness semantics or whether 'periodicity' is fixed vs. configurable, but with annotations carrying the safety burden a 3 is appropriate.

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 compact fragments with the resource and returned fields front-loaded, then the permission and endpoint. No filler sentences; every element carries information.

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 only one optional parameter, full schema coverage and annotations present, the main remaining gap was return-value shape – and the description compensates by enumerating the five returned fields. The auth scope and endpoint round it out.

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?

The single 'at' parameter is fully described in the schema (100% coverage), so the description need not repeat it. However, the description could have clarified what as-of dating means for payout figures (e.g., whether historical snapshots are supported), which is the one non-obvious semantic here.

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+resource (payout information of the LIQUID account) and enumerates the fields returned, which implicitly separates it from zettle_get_account_balance and zettle_get_account. It stops short of naming any sibling explicitly, but an agent can still tell what this tool returns.

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?

There is no statement of when to use this versus zettle_get_account_balance or zettle_list_account_transactions. The only guidance is a permission prerequisite (READ:FINANCE), which is a precondition rather than usage routing.

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