start_print

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

With no annotations, the description carries the behavioral disclosure burden. It reveals that the file must already be on the SD card and that only .3mf and .gcode are supported. However, it does not mention side effects such as whether an ongoing print is interrupted, whether the call is asynchronous, or what a successful response contains.

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 two sentences with no filler. It front-loads the core action, then gives supported file types and a minimal workflow. Every sentence contributes useful guidance.

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 13-parameter physical action with no annotations and no output schema, the description covers prerequisites and supported formats but omits return behavior, error conditions, and side effects on the printer. It is adequate for basic invocation but has meaningful gaps.

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 baseline is 3. The description adds little beyond the schema: the 'already on SD card' constraint and supported formats are already reflected in the file and path parameter descriptions. It does not explain the more complex parameters like ams_mapping or bed_type.

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 a specific action and resource: 'Start printing a file that is already on the printer's SD card.' It names supported file types and points to list_files and upload_file, which clearly distinguishes it from sibling tools such as upload_file, pause_print, or stop_print.

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?

The description gives explicit workflow guidance: use list_files to find available files or upload_file to add one first. It does not explicitly contrast with start_prints or the pause/resume/stop siblings, but the intended invocation context is clear.

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