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

Beyond the annotations (which already signal mutation), the description adds meaningful behavior: every link includes a scannable QR code, clicks/scans are tracked together, and providing qr_id changes the destination while preserving the existing short URL and printed QR code. This clarifies side effects of the update path without contradicting the annotations.

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 front-loaded with the core purpose and most sentences earn their place: example slug, use case, tracking behavior, update mode, and alternative routing. It is slightly wordy in the middle with the analytics detail, but overall well structured.

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 dual create/update behavior, the presence of an output schema, and related siblings, the description covers the essential decision points: when to use, when to use set_link_slug, the uniqueness constraint, and the preservation guarantee during updates. Nothing critical is missing for correct invocation.

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%, so the baseline is 3. The description adds value beyond the schema by explaining short_code as the branded part of the URL with an example and by clarifying that qr_id means preserving the existing short URL/QR while changing the destination.

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 states a specific verb and resource: 'Create a branded short link and dynamic QR code for an existing website URL.' It also covers the update mode via qr_id and explicitly differentiates itself from set_link_slug, so an agent can tell it apart from the closest sibling.

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?

It gives explicit when-to-use guidance: 'Use this when the user already has a destination URL and wants to shorten or brand it, track visits, or get a QR code for it.' It also names the alternative set_link_slug and the exact condition for choosing it instead, leaving no ambiguity.

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