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

Beyond the annotations, the description discloses important behavior: the API-key path returns a saved label id immediately, while the anonymous path returns a one-time link and stores nothing else. This tells the agent what happens on success and what data retention applies per auth mode, which annotations alone do not cover.

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 tight sentences, with the core purpose front-loaded before the authenticated and anonymous behavior. Every sentence adds distinct information; no repetition or filler.

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 mutation tool with no output schema, the description covers the essential missing pieces: what is returned in each auth mode, that anonymous submissions expire, and that nothing else is stored. Combined with complete schema coverage and annotations, an agent has enough to invoke it correctly.

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%, so the schema already documents all five parameters including defaults and constraints. The description adds no parameter-specific meaning beyond what the schema provides, 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?

States a specific verb and resource ('Save a ZPL label') and the exact target ('a Labelixa account'), with a clear downstream purpose ('edited, versioned and printed later'). The persistence action is distinct from all sibling preview/validate/convert tools.

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 distinguishes two calling paths: authenticated saves happen immediately, while anonymous saves are held for 24 hours behind a one-time sign-in link. It does not name sibling alternatives or say when not to use the tool, but the conditional guidance for the two modes is clear.

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