news_performance

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

Without annotations, the description carries full burden. It discloses that News does not support query dimension, a key behavioral constraint. However, it omits details like data range (days parameter), pagination (limit), and response structure, limiting transparency.

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 description is a single, efficient sentence that fronts the purpose and adds a constraint. No unnecessary words, and it earns its place with the query dimension note.

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?

Given the tool returns data (output schema exists but not detailed), the description should explain what fields are returned. It only mentions 'top pages by impressions', neglecting other potential columns. For a tool with many siblings, more context on output format is needed.

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?

With 0% schema description coverage, the description must compensate but does not. It fails to explain the 'days', 'site', or 'limit' parameters. While parameter names are somewhat clear, their roles (default values, required vs optional) are not clarified, leaving ambiguity.

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 clearly states the tool retrieves Google News performance data, specifically top pages by impressions, and explicitly distinguishes it by noting that News does not support the query dimension. This differentiates it from siblings like get_search_analytics or discover_performance.

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 for News performance data but does not explicitly state when to use this tool over alternatives (e.g., discover_performance for Discover, get_performance_overview for aggregated data). No exclusions or scenarios are given.

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