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

Annotations already declare readOnly/idempotent/non-destructive, and the description adds meaningful behavioral detail beyond them: pricing sourced from Steam lowest listing, cents as the unit, a hard cap of the first 60 skins with skin_count covering the rest, and the 'window' bounded until the next devblog. That truncation and unit disclosure is exactly the kind of context an agent needs. It does not address freshness/caching of the numbers, which would be the remaining gap.

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?

The headline sentence front-loads the payoff, then a single dense sentence traces the payload in the order an agent would care about it. Every clause carries information (source, unit, cap, window semantics); none is filler.

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?

There is no output schema, so the description carries the full burden of describing returns, and it does so thoroughly: fields, units, truncation behavior, and related entities. Combined with full schema coverage on the one parameter, an agent can call this correctly without further information.

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 100% and already documents the single slug parameter with an example, so the baseline is 3. The description earns above baseline by clarifying provenance (slug comes from get_rust_updates) and that only devblog slugs are valid, which prevents passing an arbitrary update path.

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 opens with a concrete verb-and-resource statement and enumerates exactly what is aggregated for one devblog: summary/link, per-skin price in USD cents, store-vs-drop breakdown, total value, drop collections, player peak, and prev/next links. It also distinguishes itself from get_rust_updates by naming it as the source of slugs. The generic tool name 'get_update' is rescued by the description rather than being self-evident.

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?

It gives a clear prerequisite ('Devblog slugs come from get_rust_updates') and scopes itself to devblogs only, which is the key selection signal versus other update-related tools. It stops short of explicitly stating when not to use it or naming an alternative for non-devblog update pages.

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