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

With no annotations, the description carries the behavioral burden. It usefully discloses that data is scraped daily, archived, and lacks official history, which explains staleness and date availability. However, it doesn't mention side effects (likely none) or failure behavior when a requested snapshot is missing.

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 compact sentences convey the full scope and key caveat without redundancy. The punctuation is slightly dense, but the content is front-loaded and every phrase earns its place.

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 an unannotated tool with no output schema, the description covers the main selection logic but leaves the agent guessing about default behavior when no parameters are provided, limit semantics, and the shape of the returned data. These gaps are moderate, not critical.

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 25%, but the description compensates by explaining the since options ('today's list, this week, this month') and linking date to 'past day's snapshot,' plus language to daily lists. It omits limit, though the schema's min/max partially covers that parameter.

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?

Identifies a specific resource (GitHub Trending) and enumerates all query modes: daily/weekly/monthly lists, language-specific daily lists, and archived date snapshots. The parenthetical about no official API/history further differentiates it and sets expectations.

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 clearly maps use cases to parameter choices (today/week/month to since, language to language, past day to date), making when-to-use apparent. It doesn't name alternatives, but the sibling tools are unrelated and this tool's niche is unmistakable.

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