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

With no annotations, the description carries the full disclosure burden. It usefully reveals result ordering (newest first), that items carry rank and stars-gained-today, and that limit/offset paginate. It says nothing about data freshness, upstream API dependency, rate limits, or auth, which is a meaningful gap for a tool that clearly proxies an external source.

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 dense sentence front-loads the resource and scope, then adds result shape and pagination, and closes with the routing hint. No filler, no restatement of the tool name.

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?

An output schema exists, so return-value explanation is not required, and the description still previews the key output fields. With zero annotation coverage it could say more about freshness or upstream fragility, but for a read-only listing tool with three optional params this is close to complete.

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 0%, so the description must compensate — and it largely does: it binds `days` to "last N days" and adds the 1-100 range the schema lacks, and explains `limit`/`offset` as paging controls. Defaults (7, 100, 0) are left to the schema, which is acceptable.

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 (list repositories on GitHub Trending) with scope qualifiers: last N days, newest first, ranked with stars gained today. An agent can immediately distinguish it from sibling trend tools like get_npm_trends and get_pypi_trends by the resource named.

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?

"Use when the user asks what is trending on GitHub" gives a clear triggering context. It does not, however, name an alternative tool or state when NOT to use this one (e.g., versus get_npm_trends for a package-focused question), so it stops short of full routing guidance.

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