list_processesIdentify running macOS processes sorted by high CPU or memory usage, with optional command filtering, to pinpoint resource-heavy applications.
List running processes (pid, cpu%, mem%, command), busiest first.
| Name | Required | Description | Default |
|---|---|---|---|
| limit | No | Max rows (default 30). | |
| filter | No | Only processes whose command contains this substring. |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true, so safety is covered. The description adds the ordering behavior ('busiest first') which is not in annotations, providing useful context beyond the structured metadata. It doesn't mention return format or error conditions, but for a read-only list tool, the description adds sufficient behavioral detail.
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 that states the action, the resource, the returned fields, and the ordering. There is no redundant or unnecessary text; every word adds value. Excellent conciseness.
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 read-only tool with two optional parameters and no output schema, the description covers the essential information: what is returned and how results are ordered. It does not explain pagination or platform variations, but these are minor for such a simple tool. The description is complete enough for an agent to invoke it correctly without additional guidance.
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%: both 'limit' and 'filter' have clear descriptions in the schema. The tool description adds no additional parameter context beyond what the schema provides. Since the schema fully documents the parameters, the baseline 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 states a specific verb (list) and resource (running processes) and enumerates the returned fields (pid, cpu%, mem%, command). It clearly distinguishes from siblings like list_apps (apps) and system_info (system-level metrics) by focusing on process details. This is a precise, unambiguous purpose.
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 implies usage: if you need process-level details with CPU/memory usage, use this tool. However, it does not explicitly state when NOT to use it or point to alternatives. With siblings like list_apps and system_info present, the guidance is implicit rather than explicit, so a 3 is appropriate.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.