compare_search_periods

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

With no annotations, the description carries the burden for behavioral context. It adds a useful GSC-related behavior ('Domain properties cover all subdomains') and explains how to adapt site_url plus page filtering for subdomains. Still, it does not disclose permissions, read-only/side-effect status, rate limits, or how 'top results' are ranked, leaving behavioral transparency only partially covered.

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 one-line purpose is front-loaded, followed by a tight Args list. Every line earns its place: formats, defaults, and the domain-property guidance are all necessary for correct invocation. There is no filler or repetition.

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?

The description covers all seven parameters, includes the key domain-vs-site property nuance, and the presence of an output schema covers return-value details. It is slightly incomplete because dimensions has no allowed-value list ('query', 'page', etc.) and 'top results' does not specify the ranking metric, but these are minor gaps for an otherwise well-specified tool.

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%, but the description compensates fully: site_url includes exact expected formats and examples, all four date parameters specify YYYY-MM-DD, and dimensions/limit explain their defaults and purpose. This adds substantial meaning beyond the bare schema titles.

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 starts with a specific verb and resource: 'Compare search analytics data between two time periods.' This unambiguously names the tool's operation and distinguishes it from single-period siblings like get_search_analytics, so an agent can select it without opening the schema.

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 intended use case (comparing two periods) is clear, and the site_url note correctly ties the parameter to list_properties. However, the description never explicitly says when to prefer this tool over get_search_analytics or get_advanced_search_analytics, nor states exclusions such as 'use for single-period trends instead.' The usage guidance is implied rather than stated.

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