interest_over_time

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

The description discloses important behaviors: it notes that only the first 5 keywords are used and additional ones are silently dropped, and it explains the 'isPartial' field indicating incomplete time periods. Since no annotations are provided, the description carries the full burden and adequately covers these behavioral nuances. It does not address rate limits or authentication, but for a read-only tool this is acceptable.

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 well-structured with clear Args and Returns sections, front-loads the core purpose, and uses concise bullet points. Every sentence adds information, such as the maximum keyword count and return fields, without unnecessary filler.

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 there is no output schema and no annotations, the description compensates by fully specifying the return format (date, isPartial, numeric per-keyword values) and parameter constraints. It provides everything an agent needs to call the tool correctly, including examples and edge cases, making it contextually 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?

The schema has minimal descriptions (0% coverage), but the description adds extensive semantic detail: keyword limit and silent drop behavior, example timeframe formats, and the meaning of an empty geo string. This far exceeds the bare schema, making parameter semantics highly clear.

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 returns relative Google search interest (0-100) over time for up to 5 keywords compared side by side. This is distinct from siblings like related_queries or interest_by_region, which focus on different dimensions. The specific verb and resource make the purpose unambiguous.

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 presents a clear context (temporal interest comparison) but does not explicitly state when to use it over sibling tools. It provides parameter details but no guidance on selecting this tool versus related_queries or interest_by_region. The intended use is implied by the description, not explicit.

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