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add_shape

Adds primitive shapes—circles, squares, rectangles, triangles, arrows, dots, or lines—to a Manim scene so you can build and visually verify animations.

Instructions

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": "add_shape"
  }
}

Input Schema

Name	Required	Default
`x`	No
`y`	No
`size`	No
`color`	No
`shape`	No	circle
`width`	No
`height`	No
`scene_id`	No
`project_id`	No

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Oct 24, 2026

TDQS

C2.7/5.0

Behavior2/5

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

There are no annotations, so the description carries the full behavioral burden for a mutation-like creation tool. It says what is added but not how coordinates are interpreted, whether width/height override size, what color formats are accepted, or what targeting constraints apply to scene_id/project_id.

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?

The description is a single front-loaded sentence with no filler, and the list of shape values is useful. It is efficient, though its brevity is also the source of the definition's larger completeness gaps.

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

Completeness2/5

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

For a 9-parameter creation tool with no annotations, the description is too thin. The output schema can cover return values, but the description still needs to explain targeting, coordinate conventions, and parameter interactions well enough for an agent to call it safely.

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 description coverage is 0%, and the description compensates only for the shape parameter by listing circle, square, rectangle, triangle, arrow, dot, and line. It says nothing about x, y, size, width, height, color, scene_id, or project_id, leaving most of the 9 parameters undocumented beyond their bare names.

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?

The description states a specific verb ('Add') and resource ('primitive geometry') and lists valid shape values, making the tool's basic purpose clear. It does not explicitly differentiate this tool from nearby siblings such as add_area or add_plot, but the primitive-geometry scope is still distinct.

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?

The description lists usable shape types but gives no guidance on when to choose add_shape over siblings like add_area, add_plot, or add_text. It also does not mention scene_id/project_id targeting or whether an open project/scene is required.

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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