Enhance a prompt

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

Annotations already establish readOnlyHint (safe read) and openWorldHint. The description adds genuinely useful traits beyond that: it returns text only and consumes no allowance, which is a meaningful cost/behavior signal. It omits rate limits or any length/quality guarantees.

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 tightly written sentences with the core action front-loaded and the cost/generation disclaimer second. Every clause carries information; no waste.

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?

With no output schema, the description helpfully states 'Returns text only,' covering the return shape, and the params are fully documented in the schema. It is complete for invocation purposes, lacking only detail like expected output length.

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 100% and every parameter (prompt, language, asset_type) is documented in the schema, including the enum values. The description adds no parameter-level meaning beyond the schema, so the baseline of 3 applies.

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?

Specific verb and resource: 'Expand a rough idea into a detailed prompt,' with a clear domain qualifier ('tuned for TikTok ad creatives'). It implicitly distinguishes itself from generation siblings by clarifying it produces text only, though it never names them.

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 phrase 'nothing is generated and no allowance is used' gives clear context that this is a free, non-generative pre-step, which implies when to reach for it versus the generate_* siblings. It stops short of explicitly naming an alternative or stating a when-not condition.

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