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 agentmods add skills/ppak10/rocketsmith/generate-structuresnpx skills add ppak10/RocketSmith --skill generate-structuresgit clone --depth 1 https://github.com/ppak10/RocketSmithWhat 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 | $0.00068 | $0.09827 |
| Opus 5 | $0.00034 | $0.04914 |
| Sonnet 5 | $0.00014 | $0.01965 |
| Haiku 4.5 | $0.00007 | $0.00983 |
Grade A, and why
generate-structures 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.
How it starts
The opening of the file, as written. The whole thing — 553 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Generate Structures
Overview
generate-structures is Pass 1 of the CAD pipeline. It takes a component tree and produces the base geometry for every printable part — the structural shell. Pass 2 (modify-structures) then adds detail features like holes, pockets, and mounts on top of these base STEPs.
The separation matters because:
- Iteration speed — changing a hole pattern doesn't require regenerating the structural shell
- Review boundaries — you can verify the base geometry is correct before committing to detail features
- Clean mental model — structural decisions (diameters, walls, fusion) are separate from detail decisions (retention, mounts, vents)
This skill is rocketry-agnostic — it knows about build123d and parts and assemblies, not about nose cones and fins. The manifest's feature blocks drive what gets built.
Core principle: Read the manifest, trust the manifest. Every geometric decision was made by the DFx skill. generate-structures is a faithful executor, not a designer.
When to Use
component_tree.jsonexists at<project_root>/gui/component_tree.jsonand needs Pass 1 geometry- A base STEP file is missing or out of sync with its feature block
- The user asks to regenerate structural geometry
Inputs
<project_root>/gui/component_tree.json — the authoritative parts list (populated by manufacturing_annotate_tree, never hand-edited). Specifically the parts[].features block for each part. Do not read the modifications block — that's modify-structures' job.
Output
<project_root>/cadsmith/source/<name>.py— one parametric script per part (base geometry only)<project_root>/cadsmith/step/<name>.step— the STEP file exported by each script<project_root>/gui/assets/png/<name>.png— isometric PNG thumbnail of each part for visual verification
Steps
1. Load the Manifest
manifest = read_json("<project_root>/gui/component_tree.json")
Verify it has schema_version, parts, directories, and assemblies. If anything is missing, stop and ask the design-for-additive-manufacturing skill to regenerate the manifest — do not fill in missing fields.
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 First seen · 553 lines · 68 tokens per session scan A b6c8b039fedf
generate-structures is a skill published in the GitHub repository ppak10/RocketSmith (21 stars, last pushed 4mo ago), licensed MIT. It adds 68 tokens to every session and 9,827 once invoked, about $0.0003 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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install
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