Control the printer cooling fans
| Name | Required | Description | Default |
|---|---|---|---|
| speed | Yes | Fan speed from 0 (off) to 255 (full speed). Use 0 to turn fans off. | |
| printer_id | Yes | The printer IDs (comma-separated for multiple) | |
| snippet_id | No | ID of a gcode snippet to send. Either gcode, macro, or snippet_id is required. |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate it's mutating but not destructive. The description adds no additional behavioral context such as side effects, reversibility, or prerequisites. It essentially restates the title without new information.
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 very short and front-loaded, but it adds little beyond the tool's title. It is concise but not informative, essentially a tautology. It earns a middle score for brevity without substance.
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 no output schema and three parameters, the description is insufficient. It does not explain return behavior, side effects, or clarify the ambiguous snippet_id and printer_id parameters. The tool would benefit from more context, especially given sibling tools.
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 does not add any parameter meaning beyond the schema. However, the schema has a puzzling 'printer_id' described as comma-separated but typed as integer, and the snippet_id hint references gcode/macro parameters not present in the schema. Description does not clarify these.
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 the tool controls printer cooling fans, which is clear about the resource and action. It distinguishes from siblings like set_printer_temperatures, but the verb 'control' is somewhat vague compared to 'set speed'.
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?
There is no guidance on when to use this tool versus alternatives like send_gcode or set_printer_temperatures. No context or exclusions are provided, leaving the agent without decision support.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Most tools are clearly separated by resource and action, but several overlapping queue-related tools exist—get_next_queue_item vs get_next_queue_items_for_printers, list_queue vs list_pending_queue_items, and inspect_printer_queue—which could cause misselection. list_custom_fields vs list_custom_fields_for and add_to_queue vs create_print_job add further ambiguity.
Names overwhelmingly follow a verb_noun snake_case pattern with consistent resource nouns like print_job, queue_item, folder, and filament. Minor inconsistencies exist, such as add_to_queue vs create_folder/create_print_job, save_queue_group vs update/create, and the slightly odd home_printer and send_back_for_revision.
With 74 tools, this is far beyond the recommended MCP server size and makes the toolset unwieldy to navigate, even for a broad domain. This clearly falls into the extreme 50+ tool category.
Core operational workflows—queue, print jobs, files, filament, and printer control—are well represented. However, printer lifecycle management is missing (no add/update/delete printer), and maintenance management is limited to a read-only dashboard with no corresponding actions.
