lookup_keywords

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

No annotations are provided, so the description carries the full burden. It discloses critical behavioral traits: the tool calls a paid API, results are cached for 30 days, repeated lookups are free, and the response includes meta fields to track cache vs API usage. It also instructs to inform the user before calling.

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 with three well-structured paragraphs. The first sentence states the purpose, the second adds important notes about caching and payment, and the third gives usage context. Every sentence is meaningful and front-loaded.

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?

Despite lacking an output schema, the description explains what the response contains (meta fields for cache and API counts) and the return of search volume, competition, CPC, and trends. It covers the paid API, caching, and usage context adequately for an agent to select and invoke the tool 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 description coverage is 100%, so baseline is 3. The description adds value by specifying that keywords are limited to 100 with an example array, noting that domain defaults to SEO_CLIENT_DOMAIN if not provided, and providing example location codes for US, Canada, and UK.

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 verb 'look up' and the resource 'search volume, competition, CPC, and monthly trends for a list of keywords using DataForSEO'. It distinguishes from siblings like suggest_keywords (which suggests keywords) and get_gsc_insights (which provides Google Search Console data).

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 explicitly says 'Use this to validate keyword demand during research conversations, before creating clusters' and instructs to always tell the user before calling with the number of keywords. It does not explicitly state when not to use or name alternatives, but the context is clear.

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