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

The annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, and the description's only behavioral statement, "Read only," merely restates that. It adds no context about aggregation scope, freshness of the totals, or what a caller should expect beyond the two named fields.

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 short fragments, with the substantive content (the metrics) front-loaded and no filler. The trailing "Read only" is the one element that does not earn its place, since the annotations already carry it.

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 parameters and no output schema, the description is the sole source of information about what comes back, and it names only two of the likely fields without indicating shape, grouping keys, or time window. That is enough to roughly understand the tool but not enough to predict its response confidently.

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 tool takes zero parameters, so there is nothing for the description to disambiguate; the baseline for a parameterless tool applies. The description does not misrepresent any inputs.

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 the returned metrics (active students, revenue per month) aggregated per plan, which gives some sense of the tool's output. However, it states no verb and shifts the resource name from "contracts" in the tool name to "plans" in the description, and it does not differentiate itself from close siblings like get_financial_metrics, get_monthly_closing, or list_contracts.

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 tool rather than get_financial_metrics, list_contracts, or get_monthly_closing, and no prerequisites or exclusions are given. The agent must infer the use case entirely from the metric list.

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