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

Annotations already declare this read-only, idempotent, non-destructive and closed-world, so the safety profile is covered. Beyond that, the description adds genuinely useful behavioral content: the response includes every offer in the pack plus the derivation of the up-to total, including which offers counted and which were excluded — a real disclosure about output content that annotations cannot convey.

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?

A single front-loaded sentence with no filler: resource, selector, and payload all in one pass. The parenthetical is dense but earns its place by clarifying what 'computed' means. Minor awkwardness in 'its up-to total' phrasing costs a point.

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 carries the return-value burden and largely does so — pack contents, offer list, and total derivation are all described. For a one-parameter read-only tool with full annotations this is close to sufficient; edge details like pagination or offer ordering are unstated but low-risk here.

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 there is a single parameter whose schema text already explains the slug format and points at list_packs. The description adds no further parameter meaning, so the baseline of 3 for well-covered schemas applies.

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 a specific resource (one curated pack) and selector (by slug), and states what comes back: every offer plus the total's computation basis. That distinguishes it implicitly from list_packs (many packs) and get_offer (a single offer), though no sibling is named outright.

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 only implied by the singular 'one curated pack by slug' — the agent can infer this is the detail fetch for a pack already found via list_packs, which the slug parameter's own schema text reinforces. There is no explicit when-to-use, when-not, or named alternative in the description itself.

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