Getting it into your agent
This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.
/plugin marketplace add ppak10/RocketSmith/plugin install rocketsmithWrote 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/ppak10/rocketsmith/modify-structures)<a href="https://agentmods.dev/skills/ppak10/rocketsmith/modify-structures"><img src="https://agentmods.dev/badge/skills/ppak10/rocketsmith/modify-structures/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/ppak10/rocketsmith/modify-structures"><img src="https://agentmods.dev/badge/skills/ppak10/rocketsmith/modify-structures.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00057 | $0.03698 |
| Opus 5.5 | $0.00023 | $0.01479 |
| Sonnet 5.5 | $0.00011 | $0.00740 |
| Haiku 4.5 | $0.00006 | $0.00370 |
Grade A, and why
modify-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 1mo 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 — 270 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Modify Structures
Overview
modify-structures is Pass 2 of the CAD pipeline. It takes the base STEP files produced by generate-structures and applies detail features specified in each part's modifications list: radial holes for fasteners, through-holes for screws, rectangular pockets for electronics bays, cylindrical pockets for camera mounts, vent holes, weight-relief cuts, and any other subtractive or additive detail operations that aren't part of the structural shell.
The split exists because:
- Iteration speed — changing hole positions or adding a camera mount doesn't require regenerating the structural shell
- Review boundaries — you verified the base geometry in Pass 1; Pass 2 is purely "apply these details"
- Future-proofing — rail buttons, altimeter bay cutouts, payload mounts, and custom user requests all plug into the same modification framework
This skill is rocketry-agnostic — it knows about build123d boolean operations and modification recipes, not about rockets. The manifest's modifications list drives what gets applied.
Core principle: Modifications are applied to base STEPs produced by Pass 1. Do not re-generate base geometry here. If a modification requires changing the structural shell, update the manifest's features block and re-run Pass 1.
Never edit component_tree.json directly to add or change modifications. The modifications list is populated by manufacturing_annotate_tree based on DFAM rules and user-specified overrides. If the modifications list is missing entries the user wants (e.g., rail button holes, vent holes), re-run manufacturing_annotate_tree with the appropriate parameters — do not hand-edit the JSON.
When to Use
generate-structureshas completed Pass 1 successfully- At least one entry in
manifest["parts"]has a non-emptymodificationslist - The user asks to add retention hardware, accessory mounts, vent holes, or other detail features
If every part's modifications list is empty (which is the default for a freshly generated DFAM manifest — retention defaults to "none"), skip this skill entirely.
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.
- 1mo ago First seen · 270 lines · 57 tokens per session scan A aa2d367fe3e8
modify-structures is a skill published in the GitHub repository ppak10/RocketSmith (21 stars, last pushed 5mo ago), licensed MIT. It adds 57 tokens to every session and 3,698 once invoked, about $0.0002 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 2026-08-30.
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