Retrieve valid values for field-group location rules—post types, page templates, taxonomies, options pages, and user forms—to configure where custom fields appear.
Values usable in field-group location rules: post types, page templates, taxonomies, options pages, user forms.
| Name | Required | Description | Default |
|---|---|---|---|
| site | Yes | Site id (see list_sites) |
Changes observed during successful MCP inspections.
v3.4.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. It discloses the categories of values returned, which sets expectations, but it does not explicitly state that the operation is read-only, whether it has side effects, or what the response structure looks like. For a simple retrieval tool this is minimally adequate but incomplete.
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 compact line that front-loads the value domain and contains no filler. Every word contributes to identifying what values the tool returns. The telegraphic noun-phrase style is appropriate for a simple getter.
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 one-parameter read-only tool with a fully described schema and no output schema, the description identifies the value categories but leaves the return shape (e.g., list vs. grouped object) and usage context unspecified. It is borderline adequate but an agent would still need to inspect other resources to use it confidently.
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%: the sole parameter 'site' is fully documented in the schema with a pointer to list_sites. The description adds no additional meaning about the parameter. The baseline is 3 because the schema already does the work of documenting the parameter.
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 that this tool retrieves values used in field-group location rules and enumerates the value categories (post types, page templates, taxonomies, options pages, user forms). The name supplies the verb 'get' and the resource is clear. It distinguishes from sibling schema or definition tools, though it does not state a verb or scope in the description itself.
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 offers no when-to-use guidance, prerequisites, or alternative tools. The phrase 'usable in field-group location rules' implies a context, but it does not tell an agent when to call this versus fields_get_schema, fields_list_definitions, or other field tools.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.