Write files as UTF-8 without BOM on Windows. Fixes Cursor Write encoding issues by ensuring correct UTF-8 and line endings.
Create or overwrite a file as UTF-8 (no BOM). Use instead of Cursor Write on Windows.
| Name | Required | Description | Default |
|---|---|---|---|
| path | Yes | Absolute path to the file | |
| newline | No | Line ending style (default: auto) | |
| contents | Yes | Full file contents |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are present, so the description must carry the burden of behavioral disclosure. It does disclose the key encoding trait (UTF-8 without BOM) and the overwrite semantics, but does not mention error behavior, whether parent directories are created, or line-ending handling beyond the schema's newline parameter. This covers the core behavior but leaves some operational details unstated.
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?
Two sentences, with the primary action frontloaded in the first sentence and the alternative guidance in the second. There is zero filler or redundant restatement of the schema, making it efficient and well-scoped.
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 simple write operation with only three parameters, the description plus schema provide the essential information: what it does, the encoding, overwrite behavior, and a platform condition. It could benefit from mentioning the sibling usage boundary (replace/verify) and return behavior, but no output schema exists and the tool's simplicity lowers the bar.
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%, with each parameter (path, newline, contents) having a concise description. The tool description does not repeat parameter details, but the baseline of 3 applies because the schema carries the explanatory load. No additional meaning beyond the schema is needed, though the description's 'UTF-8 (no BOM)' context hints at why newline handling matters.
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?
Description states a specific action ('Create or overwrite a file') with precise encoding behavior ('as UTF-8 (no BOM)'), which clearly distinguishes it from siblings like utf8_replace (targeted replacement) and utf8_verify (checking). It also notes the platform-specific context (Windows), reinforcing what this tool is for.
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 explicitly directs agents to use this tool instead of Cursor Write on Windows, providing a clear platform condition. However, it does not contrast against the sibling tools utf8_replace and utf8_verify, leaving some ambiguity about when a different write-family tool is appropriate. This is better than no guidance but not fully specified.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.