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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety and external-data profile are covered. The description adds genuine context beyond that: the data source (what people really type into Google), the shape of returned items (matching terms and questions with volume and difficulty), and language support (English or Arabic). It stops short of pagination/rate-limit detail, but the added value is real.

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?

Two sentences, front-loaded with purpose and output characteristics, ending with the follow-up action. No redundancy and nothing wasted.

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?

There is no output schema, so the description carries the return-value burden and does so: it describes the two result types (terms and questions) and the metrics attached (volume, difficulty). Combined with full schema coverage and clear annotations, an agent has everything needed to call it 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 coverage is 100%, so the schema already documents limit, country, and keyword, giving a baseline of 3. The description adds meaning the schema omits: the seed keyword may be English or Arabic, which tells the agent about accepted input values beyond the schema's generic 'Seed keyword' text.

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 verb+resource ('keyword ideas for a seed keyword') and characterizes the output precisely: matching terms and questions from real Google queries, each with estimated monthly volume and difficulty. It distinguishes itself from the sibling keyword_overview by positioning ideas as the exploratory step that feeds into keyword_overview.

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?

Explicitly names the context ('use for content planning') and the alternative plus the condition that routes to it ('then call keyword_overview on the best ones'). The agent knows both when to use this tool and what to do next.

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