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

Goes beyond the annotations by disclosing a rate limit ('Consumes daily quota (30/day)'), that nothing is persisted, and a parameter default. This explains why readOnlyHint is false despite 'nothing is saved' (the quota is consumed), which is genuinely useful context. It stops short of explaining auth/permission needs or what the returned option objects contain.

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?

Three short sentences, front-loaded with the core action, then persistence behavior, then quota and default. Every clause carries new information; nothing is restated from the title or schema.

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 4-parameter generation tool with no output schema, the description adequately covers what the call produces ('up to 3 options'), that it is non-destructive to content, and that it has a cost. The remaining gap is that an agent still does not know what brandId does or the exact shape/type of the returned options.

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% for 4 parameters, so the description must compensate. It clarifies the 'count' ceiling ('up to 3') and supplies the undocumented default for 'objective' ('defaults to engagement'), but 'brandId' and 'contentId' are never explained, leaving half the surface undocumented in both places.

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 concrete verb and resource ('Generate ... hook (opening line) suggestions for a content card') plus an explicit quantity cap, so the agent immediately knows this is hook copy generation, not body/caption/CTA generation. It does not explicitly name or route against its closest siblings (generate_body_options, generate_caption_options, generate_cta_options), which is what separates a 4 from a 5.

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?

'Returns options only; nothing is saved or applied' implies a non-persistent, exploratory call, and 'objective defaults to engagement' hints at configuration. However there is no explicit guidance on when to pick this over the other generate_* option tools, nor any stated prerequisites (e.g., whether a brandId or an existing content card is required).

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