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

Annotations already declare readOnlyHint=true, openWorldHint=false and destructiveHint=false, so the safety profile is fully covered. The description adds useful context — each period carries its dates and open/closed status, and the call exists to resolve ids as a prerequisite for other finance tools — but says nothing about ordering or pagination behavior beyond the schema's limit default. Adequate, not rich.

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 sentences, front-loaded with what the tool returns, followed by the downstream purpose. No filler or redundant restatement of the title.

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 two-optional-parameter, read-only list with no output schema and complete annotations, the description covers what the result contains and why the tool exists. Ordering and page-size behavior are minor omissions, with the limit default already in the schema.

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%, with the kind enum and the 'Default 24' limit documented in the schema itself. The description's mention of months/quarters/years loosely maps to the kind enum but adds no filtering semantics beyond it. Baseline 3 applies when the schema does the heavy lifting.

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: the fiscal periods a cabinet has, enumerated as months, quarters and years with dates and open/closed status. This clearly distinguishes it from finance analytics siblings like fin_cashflow or fin_forecast_variance, though it does not explicitly name a competing alternative.

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 concrete when-to-use trigger: resolve a period id before calling other finance tools. That is real routing guidance for an agent. It stops short of 5 because it does not say when not to use it or name an alternative lookup path.

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