list_devices

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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds behavioral context beyond that: LAN discovery is cached until discover_devices is run, Fleet/Dashboard printers require login, and virtual printers accept print_to_printer as a hardware-free dry run. No contradiction with the annotations exists.

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 a single long but information-dense sentence that front-loads the core purpose before enumerating categories. Every clause adds useful context, though the dry-run clause is somewhat elaborate and makes the sentence heavier than necessary.

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 read-only list tool with one optional parameter and no output schema, the description covers device categories, refresh behavior, login dependency, and virtual-printer use cases well. The main missing piece is the meaning of can_print, which would make the definition fully complete.

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?

The input schema has one optional boolean parameter, can_print, with 0% description coverage, and the description never mentions it. An agent must infer the intended filtering behavior from the parameter name alone, so the description fails to compensate for the schema gap.

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 specific verb and resource: 'List printers PreFormServer knows', then enumerates the exact printer categories: discovered LAN printers, Fleet Control queues, Dashboard printers, and virtual printers. It also implicitly differentiates itself from discover_devices by pointing out that discovery must be refreshed separately, and from physical printing by describing virtual printers as a hardware-free dry run.

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 clear context for when to use the tool: after running discover_devices for LAN printers and after login for Fleet Control/Dashboard printers. It explicitly names discover_devices as the refresh alternative, but it does not state exclusions such as when to use get_device or list_printer_types.

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