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

Beyond the readOnlyHint and idempotentHint annotations, the description discloses that results are compared with the previous period of the same length, which is a meaningful behavioral trait. It does not elaborate on output format or limitations, but the annotations already establish safety and the description adds useful context.

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 focused sentences with no filler. The key result content is front-loaded, and the practical use-case examples are placed efficiently at the end.

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 single-parameter, read-only, idempotent summary tool, the description plus schema and annotations provide complete call context. The metric list and comparison behavior are clearly stated, and no output schema exists to require further elaboration.

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 input schema has 100% description coverage for the sole parameter, including enum values and default. The description's phrase 'for a period' conceptually aligns with the range parameter but adds no new semantic detail, so the baseline score of 3 is appropriate.

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 uses a specific verb and resource: it returns headline results of the phishing-simulation programme, enumerating exact metrics (tested count, open/click/credential-submit/report rates) and period-over-period comparison. It also clearly positions itself as the starting point for high-level questions, distinguishing it from siblings like get_breakdowns and get_programme_status.

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?

The description explicitly gives usage context: 'Start here for questions like "how are we doing" or "has our click rate improved"'. This tells the agent when to use it, but it does not name alternatives or state when not to use it, so it stops short of the top score.

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