What is robot-motion?

A skill for setting up and checking robot motion from a URDF, a standard text file that describes a robot’s links and joints. It supports inverse kinematics, which calculates joint positions for a desired tool position, and path planning.

Use it to install or verify ROS 2 and MoveIt 2 dependencies, generate motion artifacts, run the motion server, test its WebSocket interface, and prepare motion-enabled URDF entries for CAD Explorer.

It provides a defined process for generating motion files, checking the local motion service, and testing robot-motion behavior. This reduces setup and debugging work when a valid robot description already exists.

How cedrickchee/text-to-cad configures Codex

Reuse

Borrowing it

Nothing to install: this file belongs to cedrickchee/text-to-cad. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/cedrickchee/text-to-cad/main/.agents/skills/robot-motion/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/cedrickchee/text-to-cad

Made for: Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/cedrickchee/text-to-cad/robot-motion.svg)](https://agentmods.dev/skills/cedrickchee/text-to-cad/robot-motion)

Your own site

<a href="https://agentmods.dev/skills/cedrickchee/text-to-cad/robot-motion"><img src="https://agentmods.dev/badge/skills/cedrickchee/text-to-cad/robot-motion.svg" alt="Measured on agentmods" height="20"></a>

Per session 87 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,106 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00087	$0.01106
Opus 5	$0.00044	$0.00553
Sonnet 5	$0.00017	$0.00221
Haiku 4.5	$0.00009	$0.00111

Measured 8d ago against content hash 715450f5f2cd, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

robot-motion scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 8d ago.

The scan reads SKILL.md. This mod also ships 17 executable files (scripts/check-motion-server.sh, scripts/conda-common.sh, scripts/gen_motion_artifacts/cli.py, …), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.agents/skills/robot-motion/SKILL.md · 71 lines

How it starts

The opening of the file, as written. The whole thing — 71 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Robot Motion

Use this skill after a robot URDF exists and the task needs local motion behavior: IK, path planning, MoveIt configuration, websocket motion-server debugging, or ROS dependency setup. Any valid repo-local .urdf can be used when gen_motion() names links, joints, frames, and end effectors that exist in that file.

Workflow

Start from an existing valid .urdf.
Generate motion artifacts from a Python source with zero-arg gen_motion() using scripts/gen_motion_artifacts/cli.py.
Verify the local motion environment with scripts/check-motion-server.sh when it may already exist; run scripts/setup.sh only when dependencies are missing or stale.
Run the websocket motion server with scripts/run-motion-server.sh.
Test protocol, artifact generation, and provider logic before handing off motion behavior.
For CAD Explorer handoff of motion-enabled .urdf entries, defer to the CAD skill and keep motion-specific metadata here.

CAD Explorer Handoff

Read .agents/skills/cad/SKILL.md, then only load its references/rendering-and-explorer.md when a task needs an Explorer URL. If unavailable, use cad-skill. Do not duplicate Explorer startup or URL syntax in this skill. Link the repo-local .urdf when motion artifacts or URDF targets were generated or changed, or when the user asks for browser review. Keep motion-specific Explorer metadata and motion-server behavior here.

Commands

Run from the robot project repository root. If the current working directory is somewhere else, set ROBOT_MOTION_REPO_ROOT to the robot project root.

python .agents/skills/robot-motion/scripts/gen_motion_artifacts/cli.py <robot-urdf-source.py> --summary

.agents/skills/robot-motion/scripts/setup.sh
.agents/skills/robot-motion/scripts/check-motion-server.sh
.agents/skills/robot-motion/scripts/run-motion-server.sh

The runtime is host-agnostic but Conda/RoboStack/Jazzy-based. The setup script creates or updates the dedicated conda environment from environment.yml, installs server/ in editable mode, and runs motion_server --check. Use any conda-compatible installation available through ROBOT_MOTION_CONDA_EXE, CONDA_EXE, PATH, or a common Miniforge/Miniconda/Anaconda install root. Do not install ROS or MoveIt packages into the repo CAD .venv, system Python, or system package managers.

Read the full file on GitHub · 71 lines

Files

What ships with it

22 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

8d ago First seen · 71 lines · 87 tokens per session scan A 715450f5f2cd

Subscribe to this mod's changes

robot-motion is a skill published in the GitHub repository cedrickchee/text-to-cad (23 stars, last pushed 3mo ago), licensed MIT. It adds 87 tokens to every session and 1,106 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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