civil-3d-skill

civil-3d-skill is a skill for OpenCode from darellchua2/opencode-config-template. It costs 43 tokens per session (1,850 once invoked), scanned A, original, Apache-2.0.

A Civil 3D workflow guide for designing corridors, surfaces, roads, pipe networks, grading, and survey work. Autodesk Civil 3D is engineering software for civil infrastructure design.

In plain words
What is it for?
Use it for version-specific Civil 3D guidance, including COM and .NET API work, after identifying the installed version.
Why use it?
It requires the Civil 3D version first because commands, locations, and available features can differ between releases.

Skill for OpenCode

Written for OpenCode: installed under .opencode/. Also seen: mentions subagents; mentions OpenCode.

Install

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.

agentmods
npx agentmods add skills/darellchua2/opencode-config-template/civil-3d-skill
Any agent
npx skills add darellchua2/opencode-config-template --skill civil-3d-skill
Clone the repo
git clone --depth 1 https://github.com/darellchua2/opencode-config-template

Made for: OpenCode.

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.

agentmods badge for civil-3d-skill

README.md
[![agentmods](https://agentmods.dev/badge/skills/darellchua2/opencode-config-template/civil-3d-skill.svg)](https://agentmods.dev/skills/darellchua2/opencode-config-template/civil-3d-skill)
Your own site
<a href="https://agentmods.dev/skills/darellchua2/opencode-config-template/civil-3d-skill"><img src="https://agentmods.dev/badge/skills/darellchua2/opencode-config-template/civil-3d-skill.svg" alt="Measured on agentmods" height="20"></a>
Per session 43 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,850 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00043 $0.01850
Opus 5 $0.00022 $0.00925
Sonnet 5 $0.00009 $0.00370
Haiku 4.5 $0.00004 $0.00185

Measured 2d ago against content hash 3704feeac9fc, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

civil-3d-skill 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 2d 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.

opencode_app/.opencode/skills/civil-3d-skill/SKILL.md · 254 lines

How it starts

The opening of the file, as written. The whole thing — 254 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Civil 3D Workflow Guidance

Provenance: extracted from civil-3d-specialist-subagent. Domain knowledge for Civil 3D corridor design, surfaces, pipe networks, and survey workflows.

CRITICAL: Version Detection (MANDATORY)

Version Prompting Rules

You MUST determine the user's Civil 3D version BEFORE providing any guidance.

If the user has NOT specified their Civil 3D version:

STOP and ask:
"What version of Civil 3D are you using? (e.g., 2026, 2025, 2024, 2023)

This is required because feature availability, UI locations, and workflows 
differ between versions. Providing incorrect version guidance could lead to 
data loss or broken models."

DO NOT proceed with any guidance until the user provides their version.

Supported Versions

Version Year Build Notes
Civil 3D 2026 2026 N.51.0 Latest - includes new corridor workflows
Civil 3D 2025 2025 N.49.0 Pressure network improvements
Civil 3D 2024 2024 N.47.0 Dynamo integration updates
Civil 3D 2023 2023 N.45.0 Connected alignments
Civil 3D 2022 2022 N.43.0 Corridor overrides

Version-Sensitive Features

These features have significant differences between versions:

  • Corridor workflows - Assembly and subassembly management changed in 2025+
  • Pressure networks - Major overhaul in 2024+
  • Dynamo for Civil 3D - Library expanded significantly in 2024+
  • Project management - Data shortcuts behavior changed in 2023+
  • Survey workflows - LINZ and local standards support varies by version

Core Expertise Areas

1. Surface Management

Creating Surfaces
  • Surface creation from DEM, contour, or point data
  • Surface analysis (elevation, slope, aspect, watershed)
  • Surface editing and smoothing operations
  • Surface boundary management
Surface Best Practices
  • Use appropriate point density for surface accuracy
  • Apply surface boundaries to limit triangulation
  • Use edit operations sparingly to maintain data integrity
  • Verify surface with contour display and visual checks

Read the full file on GitHub · 254 lines

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.

  1. 2d ago First seen · 254 lines · 43 tokens per session scan A 3704feeac9fc

Subscribe to this mod's changes

civil-3d-skill is a skill published in the GitHub repository darellchua2/opencode-config-template (6 stars, last pushed 5d ago), licensed Apache-2.0. It adds 43 tokens to every session and 1,850 once invoked, about $0.0002 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 2026-09-03.

Related

Other skills, from other repositories

gke-compute-classes

Configures, optimizes, and troubleshoots GKE ComputeClasses. Use when configuring Spot VMs with on-demand fallback, targeting specific accelerators (GPUs/TPUs) or machine families, restricting ComputeClass access, or debugging pending pods related to node pool auto-creation. Do not use for cluster-level Node Auto…

google/skills · 83 tokens

jetson-diagnostic

Read-only Jetson health snapshot for identity, memory, GPU, thermal, power, storage, services, and top processes.

NVIDIA/skills · 30 tokens

offensive-z-wave

Z-Wave attack methodology — sniffing with Z-Force / EZ-Wave / RTL-SDR + ZniffMobile, S0 (legacy) network-key derivation flaw and key reuse, S2 (modern) ECDH commissioning analysis, replay/injection on unauthenticated nodes, default-key brute-force on test deployments, and home-automation hub pivots. Use when targeting…

SnailSploit/Claude-Red · 113 tokens

holoscan-install-wheel

Install Holoscan SDK Python wheel via pip into a venv. Use for Python installs; not for native C++/apt or Conda installs.

NVIDIA/skills · 37 tokens

hyperpod-version-checker

Check and compare software component versions on SageMaker HyperPod cluster nodes - NVIDIA drivers, CUDA toolkit, cuDNN, NCCL, EFA, AWS OFI NCCL, GDRCopy, MPI, Neuron SDK (Trainium/Inferentia), Python, and PyTorch. Use when checking component versions, verifying CUDA/driver compatibility, detecting version mismatches…

awslabs/agent-plugins · 120 tokens

pcbway

PCBWay PCB fabrication and assembly — turnkey/consigned assembly, design rules, ordering workflow. Alternative to JLCPCB for manufacturing. Use with KiCad. Use this skill when the user mentions PCBWay, needs turnkey assembly (PCBWay sources parts by MPN), has parts not available on LCSC, needs assembled boards with…

aklofas/kicad-happy · 119 tokens