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

Annotations already declare a safe read-only, idempotent profile, and the description adds substantial non-obvious behavior: unsupported commands (printer settings, RFID, job management, some 2D symbologies) are skipped with warnings rather than silently, non-empty warnings imply one_to_one is false, and the output is not validated against physical printers. This is exactly the caveat context annotations cannot carry.

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?

Front-loads the conversion purpose, then layers constraints, warning semantics, and the production caveat in a logical order. It is on the longer side but nearly every clause carries actionable information; the workflow references and warning-handling rule justify their space.

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 an output schema present and rich annotations, the description supplies the missing pieces: supported/unsupported command scope, warning semantics, the one_to_one flag, and the recommendation to preview and test print. Nothing an agent needs to invoke or interpret the result is absent.

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% and each parameter already documents itself (including the DPL label_length_mm bottom-vs-top edge and the 6-inch fallback). The description only reinforces that source_language is mandatory and that readable notation like <STX>/<ESC> is accepted in `code`, adding marginal value over the schema.

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 ('Convert a SATO SBPL, Honeywell DPL or IPL label stream to ZPL') and enumerates exactly which source languages qualify. It also differentiates itself from the sibling language_detect by explaining that detect does not cover these three languages.

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 names the downstream tools (zpl_validate, zpl_preview) and the workflow order, and calls out the sibling alternative (language_detect) with the condition under which it fails. The instruction that the source language must be named is also given as a usage rule.

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