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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description adds two things annotations cannot convey: the required authorization scope ('read_catalog') and the conditional nature of the QR field, which may be absent unless previously generated.

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 short sentences with no filler, and the payload contents are front-loaded before the auth prerequisite. The first sentence is a telegraphic noun list rather than a clause, which is efficient but slightly less readable.

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 correctly enumerates the return payload (AR URL, embed URL, embed snippets, QR) and states the auth scope, which is what an agent needs to call and interpret this one-parameter read. It stops short of noting behavior when an item has no public URL or QR yet.

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% for the single 'id' UUID parameter, so the schema fully documents it. The description adds no syntax, format, or constraint detail about the identifier, so the baseline 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?

The description names the specific resource returned — public AR URL, embed URL, embed snippets, and QR — which lets an agent distinguish it from generateItemQr (which creates a QR) and getItem (which returns item data). The verb is only implied by the tool name, but the returned artifact set is concrete and unambiguous.

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?

There is no explicit when-to-use or when-not-to-use guidance, and no sibling is named as an alternative. The only conditional hint is '(if generated)', which implies QR may not exist but does not tell the agent when this tool is the right choice over getItem or generateItemQr.

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