Retrieve system environment variables with optional key filtering to inspect configuration and diagnose issues.
Get system environment variables
| Name | Required | Description | Default |
|---|---|---|---|
| filter_key | No | Filter environment variables by key name (optional) |
Changes observed during successful MCP inspections.
v1.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description must carry the full burden of behavioral disclosure. It merely restates the operation implied by the tool name and does not mention whether the operation is read-only, what the return format looks like, or whether all environment variables are returned when no filter is specified.
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 front-loaded sentence with no unnecessary words or filler. It communicates the core operation efficiently and is appropriately sized for a simple tool.
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 description is minimally adequate for a tool with one optional parameter and no annotations: it names the operation, and the schema documents the filter. However, with no output schema, the return structure is not stated, and there is no mention of default behavior when no filter is provided.
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 fully describes the sole parameter filter_key, including its purpose and optionality. The description adds no parameter information, but the schema already covers all required semantics, so the baseline score of 3 applies.
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 uses a specific verb ('Get') and a clear resource ('system environment variables'). It directly matches the tool name and is clearly distinct from sibling tools, which all pertain to networking, process, or file operations.
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 versus any alternative, and no conditions or exclusions are mentioned. The intended usage is only weakly implied by the name and description, with no explicit routing or context provided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.