DART is an open-source C++23 physics engine that simulates the movement and interactions of articulated rigid-body systems for robotics, animation, and machine learning. Researchers and developers use it for kinematics, dynamics, collision handling, constraints, and loading robot models, with C++ and Python interfaces. The catalogue add-ons support workflows built around this engine.
Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add dartsim/dart --skill dart-iogit clone --depth 1 https://github.com/dartsim/dartWrote 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.
[](https://agentmods.dev/skills/dartsim/dart/dart-io)<a href="https://agentmods.dev/skills/dartsim/dart/dart-io"><img src="https://agentmods.dev/badge/skills/dartsim/dart/dart-io/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/dartsim/dart/dart-io"><img src="https://agentmods.dev/badge/skills/dartsim/dart/dart-io.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Agent Snooping · line 7 Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
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 | $0.00027 | $0.00512 |
| Opus 5.5 | $0.00011 | $0.00205 |
| Sonnet 5.5 | $0.00005 | $0.00102 |
| Haiku 4.5 | $0.00003 | $0.00051 |
Grade A, and why
dart-io 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 3d ago.
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.
What it actually says
DART Model Loading (dart::utils)
Load this skill when working with robot model files or parsers.
When the claim depends on the loaded hierarchy, transforms, collision geometry,
or simulated behavior, also load dart-verify-sim for a text scene/behavior
oracle plus claim-tied Filament visual corroboration.
Quick Start
#include <dart/utils/urdf/DartLoader.hpp>
dart::utils::DartLoader loader;
auto skel = loader.parseSkeleton(
"dart://sample/urdf/six_axis_arm/six_axis_arm.urdf");
Full Documentation
For complete I/O guide: docs/onboarding/io-parsing.md
For repository-specific guidance: AGENTS.md
Supported Formats
| Format | Extension | Use Case |
|---|---|---|
| URDF | .urdf |
ROS robots |
| SDF | .sdf, .world |
Gazebo models |
| MJCF | .xml |
MuJoCo models |
| SKEL | .skel |
Legacy DART |
Common Patterns
#include <dart/utils/sdf/SdfParser.hpp>
// URDF with package resolution
dart::utils::DartLoader loader;
loader.addPackageDirectory("my_robot", "/path/to/my_robot");
auto skel = loader.parseSkeleton("package://my_robot/urdf/robot.urdf");
// Force specific format
auto world = dart::utils::SdfParser::readWorld("dart://sample/sdf/world.sdf");
Key Files
- URDF API:
dart/utils/urdf/DartLoader.hpp - SDF API:
dart/utils/sdf/SdfParser.hpp - SKEL API:
dart/utils/SkelParser.hpp - Tests:
tests/integration/test_DartLoader.cpp,tests/integration/test_SdfParser.cpp,tests/integration/test_SkelParser.cpp
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.
- 3d ago Changed 5efa85a8ea48
- 14d ago Changed 65c55c1cecf6
- 27d ago Changed · +10 lines · +3 tokens per session 81fb06cd52a9
- 1mo ago Changed · -4 lines 63f9fe78862c
- 1mo ago First seen · 58 lines · 24 tokens per session scan A c20580431926
dart-io is a skill published in the GitHub repository dartsim/dart (1,219 stars, last pushed yesterday), licensed BSD-2-Clause. It adds 27 tokens to every session and 512 once invoked, about $0.0001 per session on Opus 5.5. 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 2026-09-01.
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