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 behavioral context beyond annotations: the value range (0-100), volume availability, and explicit instruction to tell the user when rate limits or monthly quota are reached. No contradictions with annotations.

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 compact and front-loaded: it states the core behavior first, then usage contexts, then exclusions with alternatives, then error-handling behavior. Every sentence adds unique value with no redundancy.

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 rich input schema, output schema presence, and annotations, the description covers what an agent needs to select and invoke the tool correctly. It includes usage contexts, sibling alternatives, series characteristics, and quota/rate-limit handling. No important operational gap remains.

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 coverage is 100%, with both keyword and source already richly documented. The description mentions 'one keyword and one source' and the limit condition, but it does not add significant meaning beyond the schema's detailed per-source keyword formatting rules. Baseline 3 is appropriate because the schema carries the parameter burden.

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 opens with a specific statement of what the tool returns: 'Full historical series for one keyword and one source (0-100 values, plus volume when available).' It clearly distinguishes this tool from siblings by naming what it is not for: live trending boards go to get_top_trends and most growth questions go to get_growth.

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?

Explicit when-to-use guidance is present: 'Use for charting or custom math.' It also gives direct exclusions with named alternatives: 'Not for live trending boards (use get_top_trends)' and 'For most growth questions, use get_growth.' This makes selection unambiguous.

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