Print a photo, sketch, or diagram from your computer on a Phomemo thermal printer. The image is scaled to printer width and dithered to black and white.
Print an image file from this computer (photo, sketch, diagram). It is scaled to the printer width and dithered to black and white. Returns the job.
| Name | Required | Description | Default |
|---|---|---|---|
| path | Yes | ||
| printer | No |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. It usefully discloses that the image is scaled to printer width, dithered to black and white (a lossy, non-color transform), and that the call returns a job — but says nothing about paper/physical side effects, whether the job is queued asynchronously, or which printer is used when the optional parameter is omitted.
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 short sentences, front-loaded with the action and enriched by concrete input examples; little waste. Slightly longer than strictly necessary but every clause adds information.
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?
Adequate for a small two-parameter tool, and the processing behavior is a genuine bonus given no annotations or output schema. However, the undocumented printer parameter and unstated default-printer fallback leave a real gap 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 description coverage is 0%, so the description must compensate. It sheds some light on path (an image file on this computer) but leaves the printer parameter completely unaddressed — no default-printer behavior, no accepted value format.
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?
Specific verb + resource ("print an image file") with a clarifying parenthetical of accepted inputs (photo, sketch, diagram). It clearly differs from print_cards in substance, but never names that sibling to make the distinction explicit for the agent.
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?
Usage is only implied: the phrase "image file from this computer" suggests this tool is for raster images as opposed to print_cards, and no explicit when/when-not or alternative routing is given. An agent must infer the choice from the noun.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.