gsc_movers_and_losers

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

With no annotations provided, the description carries the full burden. It does not disclose that this is a read-only query, mention rate limits, authentication needs, or how data is aggregated. The only behavioral clue is that positive values indicate improvement.

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 concise sentence stating the purpose, followed by a well-structured parameter list. Every sentence is essential; there is no redundancy or wasted text.

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?

While the output schema exists (so return values are not needed in the description), the description omits usage context such as typical scenarios, prerequisites like GSC property access, or limitations. The parameter documentation is thorough, but broader context is missing.

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?

The description includes a docstring explaining each parameter's meaning, format (e.g., YYYY-MM-DD for dates), and defaults (top_n=25). This compensates for the input schema's 0% description coverage, adding significant semantic value beyond parameter names and types.

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 it returns pages whose position changed most between two periods, with positive meaning improvement. It differentiates from siblings like gsc_compare_periods, which likely compares overall metrics, though it does not explicitly state alternatives.

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?

No guidance is provided on when to use this tool versus other GSC tools like gsc_compare_periods or gsc_position_distribution. The description lacks any context about appropriate use cases or prerequisites.

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