Change a WordPress user's role by specifying the site, user ID, and new role (administrator, editor, author, contributor, or subscriber).
Change a user's role
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | User ID | |
| role | Yes | New role (administrator, editor, author, contributor, subscriber) | |
| site | Yes | Site id (see list_sites) |
Changes observed during successful MCP inspections.
v3.4.0Input schema / properties / siteAdded value: +{
+ "description": "Site id (see list_sites)",
+ "type": "string"
+}Input schema / requiredPrevious value: -[
- "id",
- "role"
-]New value: +[
+ "site",
+ "id",
+ "role"
+]v2.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden for a mutation operation. It does not disclose whether administrator-level capability is required, whether existing content authored by the user is reassigned, whether the change is reversible, or what the response returns.
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?
A single short sentence with no filler and the action front-loaded. It is appropriately sized but arguably too terse for a mutation tool, so not a 5.
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 destructive/mutating tool with no annotations and no output schema, the description is far too thin: no permission requirements, no side effects, no confirmation of what changes. The schema documents inputs, but the operation's behavior is left entirely unexplained.
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%, and the role parameter already enumerates all valid roles in the schema, so the description's 'role' mention adds nothing. Baseline 3 applies since the schema does all the work and the description contributes no extra parameter guidance.
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 ('Change a user's role'), which is unambiguous. However, it does not differentiate itself from the nearby sibling tool mcp_update_user, which likely also touches user fields, so the agent gets no help choosing between them.
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?
There is no indication of when to use this tool versus mcp_update_user or mcp_list_roles, no mention of required permissions, and no prerequisites (e.g., that 'site' must come from list_sites). Usage must be entirely inferred from the name.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.