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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is fully covered structurally. The description's real contribution is conceptual return-shape disclosure — the split between blocking and non-blocking findings — which matters because there is no output schema. It does not describe how findings are enumerated or how the response is organized beyond that binary.

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 sentence, zero filler, and the blocking/non-blocking dichotomy is front-loaded so the reader immediately knows the return shape. Nothing could be removed without losing 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 no output schema, the description carries the burden of explaining what comes back, and it does so at a categorical level (blockers vs. open items) while enumerating example blocker types. It stops short of describing structure or whether results are grouped, which leaves a small gap for a single-parameter read-only report 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?

The single parameter 'through' is fully documented in the schema as the last day of the period in ISO YYYY-MM-DD format, giving 100% coverage. The description restates the concept ('through a day') but adds no semantics beyond the schema, which is the expected baseline when the schema already does the work.

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?

The description names a concrete resource (close checklist) and states precisely what it surfaces: items that block closing the books through a given day versus open-but-non-blocking items. That is specific enough to distinguish it from mutation-oriented siblings, but it never explicitly contrasts itself with gl_close_period or gl_closes, so the boundary with those tools is left to inference.

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: 'what blocks closing the books' suggests calling this before attempting gl_close_period, but the description never says so, never names the alternative, and never states when this check is unnecessary. An agent must infer the pre-close workflow position itself.

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