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

The description discloses the credit consumption (15-50 CalmSEO credits), which is a behavioral trait not covered by annotations. However, it does not address the destructiveHint=true annotation; it neither confirms nor explains what destructive action may occur. With annotations present, the description adds some value but leaves ambiguity about side effects.

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 concise, two sentences, with the primary purpose stated first and the credit consumption as a secondary detail. It avoids fluff and is easily scannable. It earns its place by communicating the core function and a key operational constraint.

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 tool with 7 parameters, no output schema, and low schema coverage, the description is insufficient. It does not explain what the response looks like, how to use limit/offset, what closely_variants does, or how to interpret results. An agent would lack critical information to invoke the tool correctly, especially with destructiveHint=true remaining unexplained.

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 only 29% (only language_name and location_name have descriptions). The description does not explain key parameters like limit, offset, keywords, closely_variants, or include_serp_info. The only implicit reference is to 'result limit' in credit consumption, which hints at the limit parameter but provides no concrete syntax or semantics. This fails to compensate for the low schema coverage.

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: 'DataForSEO Labs keyword ideas for expanding seed keywords into a research set.' It identifies the specific resource (keyword ideas) and the action (expanding seed keywords). It does not explicitly differentiate from siblings like search_serp or get_keyword_search_volume, but the function is distinct enough that an agent can infer its role.

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?

No guidance is provided on when to use this tool versus alternatives. It does not mention specific use cases, prerequisites, or conditions that would lead an agent to choose it over siblings like search_serp or get_keyword_search_volume. The purpose is clear but the decision context is absent.

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