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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false. The description reinforces these but adds genuinely new behavioral context: the error-handling contract ('never raises a protocol error — it returns {"error": ...}') and safety of retry. No contradiction found.

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?

Well-structured and front-loaded with purpose, then format rules, example, usage guidance, errors, and idempotency. Slightly long with a few elements (FREE, format rules) that are not strictly necessary, but every sentence earns its place overall.

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 2-param tool with 100% schema coverage, an output schema, and strong annotations, the description is comprehensive: purpose, format constraints, worked example, usage boundaries, error behavior, and idempotency. The output schema covers return values so no duplication needed.

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% for both params, so baseline is 3. The description's worked example illustrates how title transforms into a handle and shows the collisions array, but the schema already documents both parameters thoroughly. The example adds modest illustrative value without deep new semantics.

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 a specific verb+resource: 'Turn a product title into a valid, unique Shopify URL handle.' It provides format rules (lowercase, letters/numbers/dashes) and a concrete worked example, and explicitly distinguishes itself from the sibling product_csv_check ('Not for validating a whole header row').

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?

Explicitly states when to use ('when generating handles for an import, or checking one you already have') and when not to ('Not for validating a whole header row — that is product_csv_check'), naming the exact alternative sibling tool.

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