get_ad

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

Discloses that the tool returns only a subset of ad data (not creative copy), which is a key behavioral trait beyond the readOnlyHint annotation. Also implies read-only access consistent with annotation.

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 with no waste. Front-loaded with action and resource, then efficiently adds exclusions and sibling references.

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 retrieval tool with one parameter and no output schema, the description fully covers what the agent needs: what it does, what it returns, what it excludes, and how to get missing data via siblings.

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?

Only one parameter (ad_id) with schema description 'Ad id.' The description mentions 'by id' but adds minimal extra meaning beyond what the schema already provides. Baseline 3 due to 100% schema coverage.

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?

Description explicitly states it gets one ad by ID, lists the specific fields returned (status, ad group, click-through URL), and distinguishes from siblings by noting what it excludes and directing to get_ad_creative and get_ads for other purposes.

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?

Clear when to use this tool (when needing ad metadata without creative), and when not (use get_ad_creative for creative copy, get_ads for browsing). Provides explicit alternatives.

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