Set or update a WordPress user's custom meta key-value pairs by providing the site ID, user ID, and meta object.
Update meta data for a user
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | User ID | |
| meta | Yes | Meta key-value pairs to set | |
| 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",
- "meta"
-]New value: +[
+ "site",
+ "id",
+ "meta"
+]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. It implies a write operation but does not disclose whether metadata is merged or replaced, what permissions are required, or what happens to existing keys, leaving significant ambiguity for a mutation tool.
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 short sentence with no wasted words and the core action is front-loaded. However, it is so terse that it lacks the structural detail expected for a 3-parameter mutation with a nested meta object.
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 a mutation tool with a nested meta object, three required parameters, no output schema, and no annotations, the description is too thin. It omits key operational context such as merge semantics, required permissions, and the role of the 'site' parameter.
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 each parameter's meaning. The description adds no parameter-level detail beyond the schema, making the baseline score of 3 appropriate.
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 ('Update') and resource ('meta data for a user'), making it clear this mutates user metadata rather than a user record or other resource. It does not explicitly distinguish itself from siblings such as mcp_get_user_meta or mcp_update_user, keeping it from a 5.
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 guidance on when to use this tool versus alternatives like mcp_update_user or mcp_get_user_meta, nor any prerequisites or context. The name implies a use case, but the description provides no explicit usage conditions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.