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/athola/claude-night-marketnpx agentmods add skills/athola/claude-night-market/night-market-architecture-contractWrote 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/athola/claude-night-market/night-market-architecture-contract)<a href="https://agentmods.dev/skills/athola/claude-night-market/night-market-architecture-contract"><img src="https://agentmods.dev/badge/skills/athola/claude-night-market/night-market-architecture-contract/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/athola/claude-night-market/night-market-architecture-contract"><img src="https://agentmods.dev/badge/skills/athola/claude-night-market/night-market-architecture-contract.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 | $0.00037 | $0.04737 |
| Opus 5 | $0.00018 | $0.02368 |
| Sonnet 5 | $0.00007 | $0.00947 |
| Haiku 4.5 | $0.00004 | $0.00474 |
Grade A, and why
night-market-architecture-contract 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 12d 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 — 322 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Night Market Architecture Contract
This skill records the design decisions that hold claude-night-market
together, the invariants that enforcement code keeps true, and the weak
points that are known and accepted. Read it before proposing a change
that crosses a plugin boundary, touches a hook, adds a skill, or bumps
a version. Every claim cites in-repo evidence: an ADR (Architecture
Decision Record, in docs/adr/), a commit hash, or a checked-in
enforcement file. Verify a citation before relying on it:
git log --oneline -1 <hash>
rg -n "Status" docs/adr/<file>.md
Load-bearing decisions
1. Plugins are self-contained deployables
Each of the 23 plugins under plugins/ must install and run alone.
There is no shared registry and no root-level shared library that
plugins import at runtime (ADR-0001, Accepted). Plugins detect each
other at runtime via filesystem checks and must degrade gracefully when
a sibling is absent.
Cross-plugin DRY is an anti-pattern here, and that is settled by
experiment, not taste. Commit 054e2679 consolidated 1164 lines of
duplicated tasks_manager.py from attune, sanctum, and spec-kit into a
shared root script. It broke plugin self-containment and was reverted
in 29961cd2. The durable fix, d89a55c7, made the copies
per-plugin and intentionally different. docs/dependency-audit.md
records the per-plugin copies as the approved state. Do not re-propose
the consolidation.
Practical test before you extract shared code: if a user installs only one plugin from the marketplace, does your change still work? If not, duplicate the code into each plugin instead.
2. Hooks run under host Python from a cache directory
Claude Code copies an installed plugin into a cache directory and runs
its hooks under the host system Python, which can be as old as 3.9.
The repo itself is Python 3.12 (root pyproject.toml,
requires-python >= 3.12). Only hook scripts and their transitive
import chains carry the 3.9 constraint. Five contract rules follow,
each purchased with an outage:
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.
- 12d ago First seen · 322 lines · 37 tokens per session scan A 0adc25e6adef
night-market-architecture-contract is a skill published in the GitHub repository athola/claude-night-market (337 stars, last pushed yesterday), licensed MIT. It adds 37 tokens to every session and 4,737 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 2026-08-30.
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