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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions an important cost factor ('Each keyword consumes 1 credit'), which is valuable information not available elsewhere. However, it doesn't disclose other behavioral aspects such as rate limits, error handling, or return format. The description adds some transparency but not comprehensive context.

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 two concise sentences. It leads with the action, states the purpose, and then adds the credit cost as a final note. Every sentence earns its place without unnecessary elaboration, making it efficient and easy to parse.

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 simple one-parameter tool, the description covers the core function and a key cost implication. It doesn't clarify the shape of the return value, but the phrase 'Get search volume' implies the output. Given the absence of annotations and output schema, the description is reasonably complete, though it could mention limits or typical response behavior.

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?

The only parameter is 'keywords,' and the schema provides its type (array of strings) and constrains it (minItems: 1). The description merely says 'a list of keywords,' which essentially repeats the schema without adding practical details like maximum list size, formatting, or examples. Since schema coverage is 0% (no parameter descriptions), the description should compensate but does not.

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 clearly states the tool's function: 'Get search volume for a list of keywords.' It uses a specific verb (Get) and resource (search volume for keywords), which distinguishes it from sibling tools like get_seo_traffic or get_topics. The additional context about search demand and content planning reinforces its purpose.

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 provides clear context for when to use this tool: 'to help evaluate search demand and prioritize content planning.' While it doesn't explicitly discuss alternatives or when not to use it, the context is specific enough to guide an agent. No exclusions are mentioned, but the intended use case is clear.

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