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/nrdxp/predicate/hickeynpx skills add nrdxp/predicate --skill hickeygit clone --depth 1 https://github.com/nrdxp/predicateWhat 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 | $0.00059 | $0.03972 |
| Opus 5 | $0.00030 | $0.01986 |
| Sonnet 5 | $0.00012 | $0.00794 |
| Haiku 4.5 | $0.00006 | $0.00397 |
Grade A, and why
hickey 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.
How it starts
The opening of the file, as written. The whole thing — 204 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Structural Simplicity Review
Evaluate code for structural simplicity using Rich Hickey's "Simple Made Easy" framework. Designed for a world where AI generates code faster than humans can read it — where functional tests pass but accidental complexity accumulates silently.
The core premise: tests tell you code works; they tell you nothing about whether it's simple. Hickey: "What's true of every bug found in the field? It passed the type checker... it passed all the tests." Complected code can be perfectly correct today. The damage surfaces when you try to change it, reason about it, or extend it.
[!NOTE] This workflow is the spatial half of the code-spacetime review pair. It reads code as a static snapshot — what's tangled right now? For the temporal half — what will pull apart, and when? — see
/lowy. Run both for full coverage. Seeengineering.md§8.1.
Attribution: Adapted from Rich Hickey's Simple Made Easy (Strange Loop, 2011) and Srid Ratnakumar's implementation. Full talk transcript: matthiasn/talk-transcripts.
Key Definitions
Simple (sim-plex, "one fold/braid"): One concern, one role, one concept. Simplicity is objective — count the interleaved concerns. Hickey: "What matters for simplicity is that there is no interleaving, not that there's only one thing."
Easy (adjacens, "nearby"): Familiar, at hand, within our skillset. Easy is relative. Hickey: "If you want everything to be familiar, you will never learn anything new."
Complect (com-plectere, "to braid together"): Interleave independent concerns so they cannot be reasoned about in isolation. Hickey: "Every time I think I pull out a new part of the software I need to comprehend, and it's attached to another thing, I had to pull that other thing into my mind because I can't think about the one without the other."
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.
- 2d ago First seen · 204 lines · 59 tokens per session scan A 0ab916f531f5
hickey is a skill published in the GitHub repository nrdxp/predicate (10 stars, last pushed 8d ago), licensed MIT. It adds 59 tokens to every session and 3,972 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 2026-08-31.
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