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mpfb_list_objects

Read-onlyIdempotent

List MakeHuman objects in the current Blender scene, optionally filtered by MPFB type, to find names other MPFB tools can act on.

Instructions

List the MakeHuman objects in the connected Blender's current scene, optionally filtered by MPFB object type. Changes nothing.

Use this to find a subject for the other MPFB tools when you did not create the character yourself, then pass a returned name to mpfb_get_object_info to learn what that object actually is.

object_type is one of MPFB's own type names ("Basemesh", "Skeleton", "Subrig", "Proxymeshes", "Clothes", "Eyes", "Eyelashes", "Eyebrows", "Teeth", "Tongue", "Hair"); omit it to get every MakeHuman object. Matching is MPFB's own, a case-insensitive substring test rather than equality: "rig" matches Subrig, and "mesh" matches both Basemesh and Proxymeshes. That is deliberate on MPFB's side and is not a bug here.

Only the current scene is searched, so results match what the user is looking at. An object that exists in the .blend without being linked into the scene is not listed - mpfb_get_object_info will still resolve it by name and say so.

result carries objects, one entry per match with name (the Blender object name, which is how every other tool addresses it), object_type (MPFB's type) and blender_type ("MESH", "ARMATURE", ...); count; requested_object_type, the filter as given or null; object_type_recognized, whether it matched a type MPFB knows - check this before concluding anything from an empty list, since "no basemeshes in this scene" and "you asked for Basemseh" are otherwise the same answer; and known_object_types, MPFB's full type vocabulary read from MPFB itself, so a misspelling can be corrected from this same response.

The result is an address other tools will act on. Re-call rather than cache: loading another .blend, or the user deleting an object, invalidates it entirely.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`object_type`	No

Output Schema

TableJSON Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Oct 3, 2026

TDQS

A4.9/5.0

Behavior5/5

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the safety profile is covered. The description goes well beyond that: it discloses the case-insensitive substring matching semantics (with the 'not a bug' caveat), the scene-vs-.blend linkage distinction, the empty-list/typo ambiguity, and the staleness caveat about re-calling rather than caching. These are non-obvious behavioral traits an agent would otherwise discover the hard way.

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 the core purpose and the safety statement, then builds outward to usage, matching semantics, scope caveat, result shape, and staleness. The matching-semantics paragraph is dense but every clause adds actionable information. Slightly long for a one-parameter list tool, but no true filler.

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?

Covers purpose, routing, matching semantics, scope limits, result fields including the critical object_type_recognized flag and known_object_types, and the cache-invalidation caveat. Even without an output schema being relied on here, the description explains the response structure completely enough that an agent can interpret an empty result correctly.

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

Parameters5/5

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

Schema description coverage is 0% and the parameter has no enum, so the description must carry the full burden. It does: it lists all eleven MPFB type names, states that omitting it returns everything, and explains the substring-matching semantics with concrete examples ('rig' matches Subrig). That is far more than the schema provides.

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+resource ('List the MakeHuman objects in the connected Blender's current scene'), scopes it to the current scene, and distinguishes itself from mpfb_get_object_info by naming that sibling and describing its role in the workflow. No ambiguity about what it does.

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?

Explicitly states when to use it ('to find a subject for the other MPFB tools when you did not create the character yourself') and what to do next ('pass a returned name to mpfb_get_object_info'). Also gives an exclusion ('Only the current scene is searched, so results match what the user is looking at'), and the re-call-not-cache guidance. This is textbook routing guidance.

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