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

The description adds meaningful behavioral detail beyond the readOnly/idempotent annotations: the score is cumulative, reads the whole event log at the end of each bucket, and can move even when a bucket's own rates do not. This is exactly the kind of non-obvious behavior an agent needs to interpret results correctly.

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 dense sentences carry all essential information: what is returned, how it is bucketed, when to use it, and an important behavioral caveat. There is no filler or redundancy.

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 tool with one optional parameter and no output schema, the description is largely complete: it states the metric, its scale, bucketing, and the use case. The exact return shape is not specified and the phrase 'the same rates over time' is slightly ambiguous, but an agent has enough context to select and invoke the tool correctly.

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 schema already fully documents the single enum parameter and its default. The description adds value by explaining that 30d and 90d are weekly-bucketed while 12m and all are monthly-bucketed, which is not present in the schema. This enriches, rather than merely repeats, the schema semantics.

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 clearly states the tool returns the workspace security score (0-100) and rates over time, bucketed by week or month. The phrase 'direction of travel rather than a single snapshot' explicitly positions it as a trend tool and distinguishes it from snapshot-style summaries among the siblings.

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?

It gives clear usage context: an assistant should use this when it needs to describe or chart the direction of travel over time. It also maps range values to bucketing behavior. It does not explicitly name alternate sibling tools or exclusion criteria, so it falls short of a 5.

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