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

Annotations already convey read-only, idempotent, and non-destructive behavior. The description adds 'deterministic', reinforcing idempotency. However, it does not explain what 'drafting' entails operationally, whether the results are cached, or any side effects of repeated calls. Given the strong annotation coverage, the description adds some but not extensive behavioral context.

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?

A single sentence that is concise and to the point. It efficiently communicates the core purpose and inputs. However, it omits necessary detail (e.g., output description, parameter formats) that could be added without significant verbosity. The structure is acceptable for a simple tool but front-loads the essential information.

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?

Given 4 parameters, 0% schema description coverage, and no output schema, the description is insufficient. It does not explain what 'context_hints' are, how they relate to an ad group, or what the tool returns. A user would likely need additional documentation to understand the tool's full behavior and inputs.

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 must compensate. It lists the four parameter names (product, audience, intent, keywords) but provides no additional semantics: no data types, formats, allowed values, or examples. 'keywords' has an empty JSON schema type (likely an object) but is not clarified. The parameter names are somewhat self-explanatory, but the description fails to add meaningful detail beyond the names.

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 verb 'draft' and resource 'context_hints' clearly indicate the action and output. The description specifies inputs from product, audience, intent, and keywords, making the core function unambiguous. However, it does not differentiate from sibling tools like 'get_ad_group' or 'manage_conversions', though the scope is distinct enough.

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?

No guidance on when to use this tool versus alternatives. The description lacks context about prerequisites, typical workflows, or scenarios where drafting context hints is appropriate. Sibling tools exist (e.g., 'get_ad_group', 'manage_conversions') but no comparisons are provided.

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