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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds only a light behavioral note ('returns compact rows', limit cap of 100) and the wholesale-price visibility, without describing pagination end conditions or result volume.

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 front-loaded sentences with no filler: the first establishes purpose and value, the second enumerates filters and return shape. Efficient, though the 'use limit up to 100' clause partially repeats an explicit schema constraint.

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 4-parameter, zero-required read tool with full annotation coverage and no output schema, the description gives enough to call it correctly: filters, pagination hint, and return shape. The only gap is the absence of any routing guidance against the sibling package/order tools.

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 coverage is only 50% — 'search' and 'limit' are documented, but 'page' and 'type' are not. The description compensates by explaining that 'search' is a destination name (local/regional/global type) and that 'limit' can go up to 100, covering most of the documentation gap.

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?

States a specific verb and resource ('Find eSIM data packages you can sell') and adds a distinguishing scope detail — wholesale pricing — that identifies it as the reseller catalog rather than a consumer lookup. It does not explicitly name or contrast with the sibling get_topup_packages, so it falls short of full sibling differentiation.

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 implies usage (browse sellable packages, filter by destination/type/page) and notes the return shape, but it never states when to prefer this over alternatives such as get_topup_packages, nor any exclusions or prerequisites. Usage is inferable but not specified.

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