Render one frame of an Aseprite sprite to a PNG so you can visually inspect pixel art; control frame number and scale to enlarge small sprites.
Render a single frame to a PNG and return it as an image you can view.
Use this to *see* your work. frame is 1-based; scale enlarges small sprites
(default 8x) so individual pixels are visible.
| Name | Required | Description | Default |
|---|---|---|---|
| frame | No | Default: 1. | |
| scale | No | Default: 8. | |
| filename | Yes |
Changes observed during successful MCP inspections.
v0.10.0Input schema / properties / filename / titleRemoved value: -"Filename"Input schema / properties / frame / descriptionAdded value: +"Default: 1."Input schema / properties / frame / titleRemoved value: -"Frame"Input schema / properties / scale / descriptionAdded value: +"Default: 8."Input schema / properties / scale / titleRemoved value: -"Scale"Input schema / titleRemoved value: -"render_previewArguments"v0.7.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuine behavioral context beyond that: the 1-based frame indexing and the fact that scale enlarges small sprites so pixels are visible, which tells the agent what output quality to expect.
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, zero filler, and the core action leads immediately ahead of the parameter notes. Every sentence carries 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?
With no output schema, the description correctly states the return is a viewable image, and it covers the two non-obvious parameters. Minor gaps remain (no mention of error behavior for an out-of-range frame or whether a sprite must be loaded), but nothing essential is missing for a low-complexity preview tool.
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 67% and the schema's own descriptions are content-free ('Default: 1.', 'Default: 8.'). The description compensates by explaining that frame is 1-based and that scale magnifies sprites (default 8x), adding real meaning the schema lacks; only filename is left unexplained, though it is self-evident.
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 ('Render a single frame to a PNG') plus the delivery mode ('return it as an image you can view'), which cleanly separates it from the export_* siblings that write files. An agent can identify this as the visual-inspection tool without opening a schema.
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?
'Use this to *see* your work' gives a clear condition for selection, implicitly contrasting with export tools. It stops short of naming an explicit alternative (e.g. export_png) or a when-not case, so it is clear context rather than full routing guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.