bing_keyword_history

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and openWorldHint=true, so the safety profile is covered. The description adds valuable context beyond annotations: it specifies the data granularity (weekly), the scope (one keyword), and the intended use (seasonality). It also discloses the external dependency on FREE_SEO_BING_API_KEY, which is important for the agent to know before invoking. This is meaningful behavioral context that annotations don't provide.

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 sentence that packs essential information: the data type (weekly impressions), scope (one keyword), purpose (seasonality), and a prerequisite (API key). Every word earns its place, and the most important information is front-loaded. No fluff or repetition of schema details.

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 tool has an output schema, so return values are documented elsewhere. The description covers the core purpose, the data granularity, and the API key requirement. The only minor gap is that it doesn't explain what the output looks like (e.g., a time series of impressions), but the output schema likely covers that. For a read-only, idempotent tool with a simple parameter set, this is nearly 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?

Schema description coverage is 67%: keyword has no description, while country and language have descriptions. The description adds context that the tool is for one keyword and weekly history, which helps understand the keyword parameter's role. However, it doesn't add details about the country/language parameters beyond what the schema already provides, and it doesn't clarify the expected format or constraints for keyword. Baseline 3 is appropriate since the schema covers most parameters and the description adds some context.

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: 'Weekly Bing impression history for one keyword (seasonality).' This clearly identifies what the tool does and its purpose. It is distinguishable from siblings like bing_keyword and bing_related_keywords because it focuses on historical impression trends over time, though it doesn't explicitly name those siblings.

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 implies usage context: it is for seasonality analysis of a single keyword, which suggests when to use it (when you need historical Bing impression trends). It also mentions the required API key, which is a prerequisite. However, it doesn't explicitly state when not to use it or name alternative tools for related but different needs, such as bing_keyword for current metrics or trends_compare for comparisons.

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