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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower; the description still adds real context: SerpAPI as the upstream source, the empty-result case when no keywords are tracked, and the degraded behavior when the connection or site match is missing. It does not cover latency/rate limits from the external SerpAPI dependency, but overall adds genuine value beyond the 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?

A single dense paragraph with zero filler, front-loaded on what is returned before the caveats. Every clause (field list, history_days behavior, empty-result case, connection requirement) 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 no output schema, the description carries the return-shape burden and discharges it by enumerating each field the agent will receive, plus the failure/empty modes. Nothing an agent needs to call this correctly or interpret the result is missing.

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%, so both site_id and history_days are already documented in the schema. The description restates history_days ('adds each keyword's checks over that many days') without adding syntax or format beyond the schema, so the baseline 3 applies.

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?

States a specific resource (keyword rankings SEObolt tracks for one site via SerpAPI) and enumerates the exact fields returned, including the notable outsideTop100 flag. It does not explicitly differentiate itself from close siblings such as seo__ranked_keywords or seo__keyword_metrics, leaving the agent to infer the boundary.

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?

Gives clear preconditions: the agency's SEObolt connection must exist and the site must be matched to a SEObolt site, otherwise it returns no data. It also notes keywords are added in SEObolt, not here, which wards off write attempts. It stops short of naming an alternative sibling tool to use when SEObolt isn't connected.

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