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

With no annotations, the description carries the full burden and discloses key behavioral traits: permanent vs one-time storage, retargetability, account plan limits, and authentication requirement. It also specifies the markdown table output and instructs the agent to preserve it exactly. Minor gaps around error conditions or rate limits prevent a perfect score.

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 dense sentences with no wasted words; the first sentence states the core action, and the subsequent sentences earn their place by explaining user modes and output format. Excellent front-loading and structural efficiency.

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 tool with two user modes and a specialized output format, the description covers the essential context: authentication split, persistence, retargeting, and output handling. It could mention error outcomes or exact response content, but the absence of an output schema makes the markdown instruction particularly valuable.

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?

Both parameters are fully described in the schema (100% coverage) with clear explanations of the label and URL format. The description adds no parameter-specific detail beyond the schema, so the baseline of 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 opens with a clear verb and resource ('Create a new QR code') and immediately distinguishes two user modes (authenticated vs anonymous), which differentiates it from sibling update/delete/list/scan tools. The purpose is unambiguous and specific to the creation action.

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 explains when authenticating vs anonymous invocation applies, and implies that retargeting is a separate operation (update_qr_target). It also provides explicit output handling guidance. However, it does not name sibling tools directly or state when not to use this tool, so it stops short of a full when/when-not comparison.

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