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

Annotations already declare readOnlyHint=false, idempotentHint=false and destructiveHint=false, so the mutation profile is covered. The description adds the useful operational note that at least 3 values are recommended and that the asset only takes effect once linked, but says nothing about validation failures, account permissions, or what happens on duplicate creation.

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 purpose sentence, then a clarifying example, then per-argument notes. Every section earns its place, though the Args/Returns scaffolding is slightly verbose for only three parameters.

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 3-parameter mutation tool with full annotation coverage and an output schema, the definition supplies the essential enum, format constraints, and linking context. The only real gap is guidance on what happens when creation fails or the header/values pair is rejected.

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 0%, so the description carries the full burden and does it well: it documents the numeric-only, hyphen-free format for customer_id, enumerates the complete allowed header list (the schema has no enum at all), and gives the minimum-values recommendation for the values array.

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 first sentence states a specific verb and resource ('Creates a structured snippet asset') and adds where it can be applied (campaigns or ad groups). The concrete example (header 'Brands' with values ['Nike', 'Adidas', 'Puma']) makes the asset type unmistakable against the many other create_*_asset siblings.

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 notes the asset 'can be linked to campaigns or ad groups', which hints at the follow-up linking workflow, but it never states when an agent should choose this asset type over create_callout_asset or create_sitelink_asset, nor any exclusions or prerequisites. Usage context is implied rather than prescribed.

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