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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, destructiveHint=false. The description adds value beyond these by disclosing pricing ($0.001 per call, paid via x402) and detailing the exact checks performed, which informs the agent about cost and scope.

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 a single dense paragraph with no wasted words. It front-loads the main purpose ('Alt-text audit for any page') and efficiently lists all specific checks. Every sentence earns its place.

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 the tool's complexity (multiple types of alt-text issues), a single parameter, and an existing output schema, the description provides a complete overview of what the tool checks. It covers all relevant aspects without needing to explain return values, which are handled by the output schema.

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 100% with a single parameter 'url' described as 'Public URL of the page to audit'. The description adds minimal meaning beyond the schema, stating 'any page' which aligns with 'Public URL'. Baseline 3 is appropriate as the schema adequately documents the parameter.

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 clearly states it's an alt-text audit and enumerates specific issues detected (missing alt, filename-as-alt, generic alt, over-long alt, unlabeled SVG, image-map areas, image inputs, decorative alt counts). This distinguishes it from sibling SEO tools like get_seo_full_audit or get_seo_head_check, which cover broader aspects.

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 explicitly targets 'SEO and accessibility agents', providing clear context for use. While it doesn't state when not to use or mention alternatives, the specific scope of alt-text audit implies it's complementary to other SEO tools. This is sufficient for an agent to select it appropriately.

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