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

Annotations already declare readOnly/idempotent/open-world, so safety is covered. The description adds real value beyond them: the data is LIVE from public ad libraries, only publicly available creatives/copy are returned, and the Meta path requires a connected account (auth prerequisite).

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?

Front-loaded with the core purpose, then platform details and the negative-keyword caveat. Dense but each clause contributes; the platform list is compact and readable.

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?

Output schema exists so return format needn't be described, and annotations cover the safety profile. The description supplies the important operational caveats (live public data, auth requirement for Meta), leaving only the non-platform parameter semantics thin.

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 0%, so the description carries the param burden. It documents the platform enum values well and implies the query is a brand/domain, but leaves limit and region (default TR) entirely unexplained. Partial compensation only.

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 (fetches) and resource (a brand's/domain's LIVE ads from public ad libraries), with the platform scope enumerated (google/meta/linkedin). It is clearly distinguishable from sibling data tools like seo_paid_keywords or keyword_opportunities because it targets competitors' live ad creatives from public libraries.

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?

Gives clear context for each platform path, including the prerequisite that meta requires a connected Meta account, and a useful exclusion (competitors' organic keywords are NOT available). It stops short of naming a specific alternative tool to use instead for organic keywords, so no explicit routing.

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