Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/vibeic/vibe-icnpx agentmods add skills/vibeic/vibe-ic/design-for-ecoWrote 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/vibeic/vibe-ic/design-for-eco)<a href="https://agentmods.dev/skills/vibeic/vibe-ic/design-for-eco"><img src="https://agentmods.dev/badge/skills/vibeic/vibe-ic/design-for-eco/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/vibeic/vibe-ic/design-for-eco"><img src="https://agentmods.dev/badge/skills/vibeic/vibe-ic/design-for-eco.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00180 | $0.02518 |
| Opus 5 | $0.00090 | $0.01259 |
| Sonnet 5 | $0.00036 | $0.00504 |
| Haiku 4.5 | $0.00018 | $0.00252 |
Grade A, and why
design-for-eco 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 11d 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 — 180 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Design-for-ECO — spare-cell / spare-gate / spare-pad readiness
A taped-out chip will, sooner or later, need a fix: a missed timing path, a logic bug found in bring-up, a metal-mask trim. The cheapest possible fix is a metal-only ECO — reusing already-placed transistors and only re-spinning a few metal/via masks. The most expensive is a base-layer respin — new diffusion/poly masks, a full mask set, weeks of fab time. Design-for-ECO is the discipline of pre-investing a small amount of silicon area, BEFORE tape-out, so that future fixes stay in the cheap (metal-only) regime.
This skill is chip-AGNOSTIC: it describes the methodology and the hard preservation rule; the deterministic insertion + verification is owned by the phase3 stage3 Design-for-ECO step and its two checkers (see Flow integration).
Why pre-place spare cells/gates + reserve spare pads
| Fix vehicle | Masks touched | Relative cost / turn time | Needs spares? |
|---|---|---|---|
| Metal-only ECO | a few metal + via | low — days, partial mask set | yes — must reuse existing transistors |
| Base-layer ECO | poly/diffusion + all above | high — weeks, full mask set | no (but expensive) |
| Full respin | entire mask set + re-PnR | highest | no |
A metal-only ECO can only add/replace logic if the transistors it needs are already on the die (placed, powered, tied off) and only need re-wiring. If no spare cells exist near the bug, even a one-gate fix forces a base-layer respin. The same logic applies at the chip boundary: a missing test/trim/config signal after tape-out needs a reserved spare pad (and its ESD + bond option) already present — you cannot add a pad in metal only.
So Design-for-ECO trades ~1-5% area + a handful of pads now for the option to do almost any late fix as a metal-only spin later. On most projects that option is exercised at least once and pays for itself many times over.
What to insert
Spare standard cells / gates (the ECO pool)
Insert a mix of cell types so an arbitrary future fix can be assembled from nearby spares without re-placing:
What ships with it
2 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.
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.
- 11d ago First seen · 180 lines · 180 tokens per session scan A a5c1ce9e0238
design-for-eco is a skill published in the GitHub repository vibeic/vibe-ic (23 stars, last pushed today), licensed Apache-2.0. It adds 180 tokens to every session and 2,518 once invoked, about $0.0009 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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