Fetch the editor form schema for a chosen definition kind before creating or updating field groups, post types, taxonomies, or options pages.
Editor form schema of one definition kind (fields and their options). Read it before fields_create_definition / fields_update_definition.
| Name | Required | Description | Default |
|---|---|---|---|
| kind | Yes | Definition kind: field groups, post types, taxonomies or options pages | |
| 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?
With no annotations, the description carries the full burden. It discloses the workflow dependency (call before create/update) and implies a read-only schema fetch, but says nothing about permissions, whether the schema varies per site/kind, or any rate/access constraints.
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?
Two sentences, zero filler, with the resource stated first and the routing instruction second. Every clause earns its place.
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 two-param, read-only schema getter with no output schema, the description is nearly sufficient: it states the resource and the workflow position. It stops short of hinting at the schema's shape, which would help since no output schema exists.
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 kind enum is fully documented in the schema, so the baseline is 3. The description adds only "fields and their options" about the return, not new meaning for the site or kind parameters.
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?
Names a specific verb and resource: retrieve the editor form schema for one definition kind, with a parenthetical clarifying it returns fields and their options. This distinguishes it from sibling readers like fields_get_definition and fields_list_definitions, though it doesn't explicitly contrast 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?
"Read it before fields_create_definition / fields_update_definition" gives explicit ordering guidance that selects this tool over its siblings. No when-not conditions or prerequisites are stated, but the sequencing rule is unambiguous.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.