Retrieve extension groups from a Yeastar P-Series PBX to view group names and member details. Supports pagination for large systems.
List extension groups.
| Name | Required | Description | Default |
|---|---|---|---|
| page | No | Page number (1-based). Defaults to 1. | |
| page_size | No | Items per page. Defaults to the PBX's own default page size. |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the burden of behavioral disclosure. It only says 'List extension groups,' which conveys the basic action but does not disclose pagination behavior beyond what the schema already says, nor any filtering, ordering, or response characteristics. The description adds minimal behavioral value beyond the tool name and schema.
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 sentence that front-loads the core action. It has no fluff or redundancy. It loses one point because it could have also included the list-vs-get distinction concisely.
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?
Given no annotations and no output schema, the description is thin. It names the resource but does not cover pagination semantics, default page size behavior, sorting, or how it differs from the single-group getter. For a straightforward list tool, this is minimally viable but not complete.
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%, so the schema already documents both parameters. The description adds no additional parameter meaning, but the schema carries the load adequately. The baseline of 3 is appropriate because the description doesn't improve parameter understanding but the schema compensates.
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 and resource: 'List extension groups.' This clearly identifies the primary action of retrieving extension group entries. However, it doesn't distinguish itself from the sibling tool yeastar_get_extension_group, which is a related operation; a mention of the list vs. get distinction would have made it fully clear.
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 about when to use this tool versus alternatives. There is no mention of when a list operation is appropriate, no exclusion criteria, and no pointer to yeastar_get_extension_group for retrieving a single group. The tool's name suggests a listing utility, but the description leaves usage decisions entirely to the agent.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.