Save edited images to .png, .jpg, .webp, .avif, or .tif files, with optional transparency, scale, quality, and region export. Use only when the user requests saving a finished image.
Write the image file (.png .jpg .webp .avif .tif). ONLY when the user asks for it. transparent=true keeps alpha (png/webp). box exports a region.
| Name | Required | Description | Default |
|---|---|---|---|
| box | No | ||
| path | Yes | ||
| scale | No | ||
| project | No | ||
| quality | No | ||
| transparent | 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 behavioral burden. It discloses the write action and that transparent=true preserves alpha (png/webp) and box exports a region, but says nothing about overwrite behavior, permission/format constraints on path, or what happens to an existing file.
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 tight sentences, front-loaded with the core action before the usage constraint and parameter notes. No filler, though the parenthetical format list is slightly peripheral.
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 6-parameter file-writing tool with no annotations and no output schema, the description covers the essential action and the most consequential flags but omits return/overwrite semantics and the role of scale, quality, and project. Adequate but with clear 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?
With 0% schema description coverage across 6 params, the description must compensate but only covers transparent (alpha retention) and box (region export), plus implicitly path. It leaves scale, quality, and project completely undefined, so half the parameters have no semantics anywhere.
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 ('Write the image file') and resource (image file, with enumerated formats), which is clearly distinct from siblings like project_save or preview. It does not explicitly name a sibling it replaces, but the write-to-disk action is unambiguous.
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?
Gives an explicit when-to-use constraint ('ONLY when the user asks for it'), which meaningfully guards against unsolicited exports. It does not name an alternative tool or describe when another export path is appropriate, so it stops short of full routing guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.