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by FredMichel
OverviewSchemaSourceRelated ServersDiscussionsAdmin
Python
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render_scene

Render a scene to video and sampled frames, then run verification lanes to detect and fix incorrect renders before export.

Instructions

Render one scene to video + sampled frames, then run verification lanes.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "render_scene"
  }
}

Input Schema

NameRequiredDescriptionDefault
scene_idNo
project_idNo

Output Schema

NameRequiredDescriptionDefault

No arguments

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.1.0

TDQS

B3/5.0
Behavior3/5

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

With no annotations, the description carries the full burden, and it does disclose non-obvious compound behavior: this is a heavy render that emits both a video and sampled frames and then triggers verification lanes. However, it says nothing about prerequisites (open project, existing scene), runtime/cost, whether existing artifacts are overwritten, or failure modes of the verification step.

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?

A single front-loaded sentence with the action first and outputs after; no wasted clauses. "Verification lanes" is unexplained jargon, which is the only real structural weakness.

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

Completeness3/5

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

The existence of an output schema relieves the need to describe return values, and the compound render-then-verify flow is captured. But for an expensive, side-effecting, zero-annotation tool with two undocumented optional parameters, the description leaves too much unsaid about prerequisites and parameter meaning.

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

Parameters2/5

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

Schema coverage is 0% and both parameters (scene_id, project_id) are optional with null defaults. The description never explains what each identifies, what happens when either is null, or how they interact — exactly the ambiguity that most needs description support.

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

Purpose4/5

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

States a specific verb and resource ("Render one scene") plus two concrete outputs (video, sampled frames) and a follow-on step (verification lanes). It clearly implies it is not the single-frame sibling, though it never names render_frame, so differentiation is inferred rather than stated.

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

Usage Guidelines2/5

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

No when-to-use, when-not, or alternative routing is given. The phrase "one scene" hints that project-wide rendering is out of scope, but an agent gets no guidance on choosing this over render_frame, export_gif, or inspect_render.

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

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