get_time_series

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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, so the safety profile is covered. The description adds meaningful behavior beyond those annotations: the historical series is bounded to 0-100 values, may include volume, and rate limits or quota exhaustion should be surfaced to the user as a plan-limit message.

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 three sentences with no filler: the core function is front-loaded, usage alternatives are given next, and the rate-limit instruction is a distinct actionable note. Every sentence 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?

With an output schema present, the description does not need to explain return values in depth. It covers the purpose, scope, alternatives, sibling routing, and an important error-handling behavior, making it complete for an agent to select and invoke the tool correctly.

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 100%, and the input schema already contains highly detailed parameter docs, especially for keyword formats per source. The description adds only minor context like 'one keyword and one source,' which mostly restates the schema's 'Exactly one source per request,' so the description does not need to compensate further.

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 states a specific verb and resource: 'Full historical series for one keyword and one source (0-100 values, plus volume when available).' It also explicitly distinguishes itself from sibling tools by naming get_top_trends and get_growth, so an agent can immediately tell what this tool is for.

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 gives direct usage guidance: 'Use for charting or custom math' and explicitly says not for live trending boards, redirecting to get_top_trends. It also routes growth questions to get_growth and provides rate-limit/quota handling instructions, leaving little ambiguity about when to invoke this tool.

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