run_autocomplete

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

Annotations indicate readOnlyHint=false, idempotentHint=false, and destructiveHint=false, which is ambiguous; the description compensates by stating that each call consumes one autocomplete query and one API request, a valuable quota/cost disclosure. However, it does not describe response format or failure behavior, and lacks any note on whether the operation is read-only.

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, every sentence earns its place: the first defines the operation and stores, the second adds practical use and quota cost. No filler or repetition.

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 4-parameter lookup with full schema coverage and a clear cost warning, the description is mostly complete. It does not describe return values or how to interpret autocomplete results, but no output schema exists, which is a minor gap. Overall adequate for a straightforward tool.

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%, with each parameter (store, country, lang, prefix) already documented in the input schema. The description adds no extra semantic detail beyond the schema except prefix length, which is already in the schema. Baseline 3 applies because the schema does the heavy lifting.

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 fetches autocomplete suggestions from App Store or Google Play for a given prefix, with a specific character range. It names both stores, matching the GPLAY/ITUNES enum, and the 'discover what users are searching for' framing adds practical purpose. This distinguishes it from sibling tools like inspect_keyword or top_charts.

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 indicates this is useful for discovering user search terms starting with a seed, and notes it consumes one autocomplete query and one API request. Sibling names show alternatives like get_keyword_rank_history or top_charts, but the description does not explicitly state when not to use it compared to those tools. Still, the usage context is clear enough.

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