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describeType

Get the complete specification for an entity kind. Verify its registration and structure to ensure proper reuse before defining or minting new entities.

Instructions

Describe a single entity kind in full: displayName, description, parent (extends), child kinds, external-vocabulary aliases (sameAs), provenance lane, and how many entities currently carry it. The deep counterpart to introspect's cheap kind index — call it to confirm a kind's shape and reuse before minting a near-duplicate with defineEntityKind, or before createEntity. Accepts a canonical name (person, user:vehicle) or a bare local name (vehicle) that resolves to the user: kind when unambiguous. Returns E_NOT_FOUND with near-name suggestions when the kind is not registered.

Input Schema

Name	Required	Description	Default
`name`	Yes	Entity kind to describe, e.g. person or user:vehicle. A bare local name (vehicle) also resolves to the user: kind when unambiguous.

Output Schema

Name	Required	Description
`name`	Yes	Canonical kind name, e.g. user:vehicle.
`parent`	No	Parent kind in the subtype hierarchy (extends). Absent for root kinds.
`sameAs`	No	Alias IRIs to external vocabularies (schema.org, Wikidata, FOAF, …).
`addedBy`	Yes	Who registered the kind: seed, llm, user, or extension.
`children`	No	Registered kinds that extend this one.
`provenance`	Yes	Namespace lane: core, user, or extension:<name>.
`usageCount`	Yes	Number of entities currently carrying this kind.
`description`	Yes	One-sentence explanation of the kind.
`displayName`	Yes	Human-readable label.
`propertySchema`	No	JSON Schema for the kind's typed properties (attr_schema). Present only when the kind declares typed properties; use this to validate or populate the properties field in createEntity.

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Oct 31, 2026

TDQS

A4.4/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are present, so the description carries the full burden, and it does disclose real behavior: name resolution semantics, the E_NOT_FOUND failure mode with near-name suggestions, and the depth of the returned record. It stops short of stating permission/auth requirements, which for a read tool is a minor gap rather than a serious one.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with what the tool returns, then usage routing, then input resolution and error behavior — a sensible order with no filler sentences. The field enumeration overlaps with the output schema, which is slight redundancy but still aids scanning.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a single-parameter read tool with an output schema and no annotations, this covers everything an agent needs: what it returns, when to prefer it over siblings, how names resolve, and what happens on failure. Nothing material is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the baseline is 3. The description's note about a bare local name resolving to the user: kind when unambiguous largely restates the schema's own parameter description, adding little beyond it.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb (describe) and resource (a single entity kind) and enumerates exactly what is returned: displayName, description, parent, child kinds, sameAs aliases, provenance lane, entity count. It explicitly differentiates itself from introspect's 'cheap kind index', so an agent can distinguish it from the sibling without opening a schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives concrete when-to-use triggers: confirm a kind's shape and reuse before minting a near-duplicate with defineEntityKind, or before createEntity. It also names the cheaper alternative (introspect) and the condition that selects it, leaving nothing to inference.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.