Run any npm script from your package.json. Specify the package directory, choose a script, and pass arguments. Omit script name to view available scripts.
Run a script defined in package.json
| Name | Required | Description | Default |
|---|---|---|---|
| args | No | Arguments to pass to the script | |
| path | Yes | Absolute path to the package directory | |
| script | No | Script name to run (omit to list available scripts) |
Changes observed during successful MCP inspections.
v1.2.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries full burden for behavioral disclosure. It only states it runs a script but does not describe side effects, execution context, permission requirements, or whether it is synchronous. This is insufficient for a tool that executes code.
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 a single, concise sentence. It is front-loaded and efficient, but could include more critical information without being overly verbose.
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?
The tool has 3 parameters and no output schema, yet the description is minimal. It does not explain the return value (e.g., exit code, output), error handling, or behavior when the script fails. More context is needed for safe usage.
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?
The input schema has 100% description coverage, so the description does not need to add much. It mentions 'script defined in package.json' which aligns with the schema but adds no new meaning beyond the parameter descriptions.
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 clearly states the tool's purpose: to run a script defined in package.json. The verb 'run' and resource 'script defined in package.json' are specific, and it distinguishes itself from sibling npm commands like install or publish.
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 provides no guidance on when to use this tool over alternatives (e.g., npm run). It does not mention when to list scripts vs. run one, nor does it explain prerequisites or limitations.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.