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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), yet the description adds real value: cancelled sales are not retrievable, and listing text is untrusted data (a prompt-injection guard). It does not say whether a cancelled/unavailable sale returns an error or an empty result, which would complete the picture.

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 constraints, then a security note. Every sentence carries weight, though 'its latest updated_at revision' is slightly opaque phrasing that could be tightened.

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 read-only, one-parameter tool with no output schema, the description covers availability, freshness, and content-safety concerns. The only real gap is ambiguity about the failure mode for cancelled or missing sales, which matters for an agent's next step.

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 single required parameter (slug) has 0% schema description coverage; only a regex pattern conveys format. The description says 'one public sale' but never explains what the slug is or where it comes from, so the agent gets no semantic meaning for the one input it must supply.

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 specific verb and resource ('Read one public sale'), plus the scope qualifier that it returns the latest updated_at revision. The singular 'one' implicitly separates it from search_sales, but no sibling is named explicitly, so the differentiation is left to inference.

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?

'before making changes' gives a clear usage condition that routes the agent here prior to update_sale or cancel_sale, and 'Cancelled sales are unavailable' sets an exclusion. It stops short of naming the alternative tools or stating what to do when a sale is cancelled.

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