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

The annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, and the description's 'Read-only and safe to repeat; it changes nothing' largely restates them rather than adding new traits. It does add genuinely new context (prices are denominated in EUR, and the response covers billing periods and inclusions), which is useful since there is no output schema.

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 tight sentences that front-load the payload before the safety note, with no filler. The closing clause 'it changes nothing' is mildly redundant with 'Read-only' and with the annotations, costing it the top mark.

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 usefully sketches the response shape (prices, billing periods, inclusions) and the currency. The one gap is that it says nothing about the country parameter's effect on which price list is returned, which matters for interpreting the prices.

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 description coverage is 100% and the single country parameter is fully documented there (ISO code, default NL), so the baseline is 3. The description never mentions the country parameter or that it selects the price list, so it adds no meaning beyond the schema — though it does clarify the currency of the returned prices.

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?

Clear verb+resource ('All current course packages') plus a specific payload enumeration (live prices, billing periods, contents), so an agent knows exactly what it returns. It does not explicitly name the sibling get_package as the single-package alternative, so sibling differentiation is only implied by 'All current'.

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: 'All current course packages' signals this is the bulk-listing call and get_package is the single-item counterpart, but no when-to-use, when-not, or alternative tool is named. Adequate but leaves routing to inference.

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