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

Without annotations, the description carries the full behavioral burden. It discloses key behaviors: 'extracts on-image text, evaluates prominence/contrast/dark patterns/disclosures, and returns a full audit'. This gives a solid understanding of processing steps and outputs, though it omits failure modes and side effects.

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?

The description is two sentences, front-loading the main purpose and then efficiently covering inputs and behavior. Every sentence earns its place without redundancy or wasted words.

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 five optional parameters and no output schema, the description provides useful usage patterns but leaves ambiguity about parameter combinations (e.g., what happens if multiple inputs are passed together). The listed evaluation criteria and 'full audit' output give a good overall sense of the tool's behavior.

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?

The schema already has 100% parameter coverage, so the baseline is 3. The description adds value by clarifying input relationships: 'Pass an image URL, base64 image, or just a landing-page URL plus caption', which implies mutual alternatives and a common usage pattern beyond individual parameter definitions.

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 description opens with 'Cross-jurisdiction ad-creative compliance scan (~30 rules)', giving a specific verb phrase ('compliance scan') and a clear resource (ad creatives). It distinguishes itself from sibling compliance check tools by targeting ad creatives specifically, and further clarifies the output ('returns a full audit').

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 provides explicit input alternatives: 'Pass an image URL, base64 image, or just a landing-page URL plus caption'. This gives clear context on what arguments to provide and how they combine, though it does not explicitly name alternative tools or exclusion conditions.

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