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

Annotations already indicate read-only and non-destructive, but the description adds substantial behavioral context: keyless access to Google Suggest, two expansion levels, heuristic intent clustering, volume bucketing with explicit 'ESTIMATED' labeling, cache TTL of 6 hours, and output details. This exceeds what annotations provide and gives the agent a strong understanding of side effects and caveats.

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 dense and well-structured: purpose, methodology, output, options, caching, and ICP in sequence. It is longer than minimal, but each sentence conveys useful information. Minor redundancy (keyless mentioned twice) prevents a perfect score.

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 description covers the tool's function, external data source, output fields, volume estimation behavior, geographic/language targeting, caching, and intended audience. Given the existence of an output schema and annotations, this is complete for a moderately complex tool. No critical gaps remain.

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%: every parameter (seed_keyword, country, language, async) is described in the input schema. The description adds minor context about country/language targeting and the seed keyword concept, but it does not need to compensate for missing schema info. Baseline 3 is appropriate.

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 what the tool does: 'SEO keyword research from a seed keyword or topic.' It goes further to describe the method (Google Suggest), output (intent clusters, quality scores, opportunities), and distinct features (keyless, estimated volumes), which distinguishes it from siblings like seo_cro_audit.

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 the tool: given a seed keyword or topic, it returns research for SEO/content planning. It also names target users (SEO managers, content strategists, etc.), but it does not explicitly mention when not to use it or how it compares to alternative tools. That keeps it at 4 rather than 5.

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