Citable — a domain's footprint month by month

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

Beyond the readOnlyHint and openWorldHint annotations, the description adds cost ($0.03 per call), partial-month caveat, statelessness ('nothing is stored'), and 'not charged on failure' — all useful operational details that help an agent set expectations. These are not redundant 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 front-loaded with cost and core purpose, then lists metrics and unique attributes, ending with a routing note. Every sentence earns its place; it is dense but not bloated, and the structure leads with the most important decision-relevant information.

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?

For a read-only tool with no output schema, the description covers what data is returned (provided metrics), the time granularity, the caveat about partial month, and pricing. It could mention pagination or response structure, but given the simplicity and openWorldHint, it is sufficiently complete for an agent to invoke 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 coverage is 100% and each parameter has a description. The description adds value by tying the 'months' parameter to 'the current month may be partial,' clarifying how the range affects data interpretation — meaning beyond what the schema states. This is above the baseline 3.

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 clear purpose: it shows a domain's organic footprint changes month by month, listing concrete metrics (keywords ranked, top-10 count, traffic, value, keyword movements) and explicitly contrasts with citable_rank_check for single-keyword today. This distinguishes it from sibling tools and gives a specific verb+resource.

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?

It explicitly states when to use (tracking monthly history of rankings) and when not ('for one keyword's position today use citable_rank_check'), naming the alternative and the condition. This provides clear guidance for tool selection.

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