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 skills add oliver-kriska/claude-elixir-phoenix --skill phx-boundariesgit clone --depth 1 https://github.com/oliver-kriska/claude-elixir-phoenixWrote 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/oliver-kriska/claude-elixir-phoenix/phx-boundaries)<a href="https://agentmods.dev/skills/oliver-kriska/claude-elixir-phoenix/phx-boundaries"><img src="https://agentmods.dev/badge/skills/oliver-kriska/claude-elixir-phoenix/phx-boundaries/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/oliver-kriska/claude-elixir-phoenix/phx-boundaries"><img src="https://agentmods.dev/badge/skills/oliver-kriska/claude-elixir-phoenix/phx-boundaries.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 | $0.00035 | $0.01113 |
| Opus 5 | $0.00017 | $0.00557 |
| Sonnet 5 | $0.00007 | $0.00223 |
| Haiku 4.5 | $0.00003 | $0.00111 |
Grade A, and why
phx-boundaries 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 6d 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.
This is a copy
91% identical to boundaries — 25 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 138 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Phoenix Context Boundary Validation
Analyze module dependencies to ensure clean context separation and proper architectural boundaries.
Usage
phx-boundaries # Check for violations
phx-boundaries --assess # Score context health (0-100)
phx-boundaries --fix # Suggest fixes for violations
--assess Mode: Context Health Score
Evaluate overall boundary health with a quantified score.
Metrics Calculated
| Metric | Healthy Range | Red Flag | Weight |
|---|---|---|---|
| Modules per context | 3-15 | >20 or <2 | 20% |
| Public API surface | 5-30 funcs | >40 funcs | 15% |
| Fan-out (contexts called) | 1-4 | >6 | 20% |
| Fan-in (called by contexts) | 1-6 | >10 | 15% |
| Circular dependencies | 0 | >0 | 15% |
| Boundary violations | 0 | >0 | 15% |
Commands for Assessment
Use Glob to count .ex files per context directory under lib/my_app/*/.
Use Grep to count public function definitions per context file under lib/my_app/*.ex.
Run mix xref graph --format stats for dependency analysis.
Run mix xref graph --format cycles --label compile for compile-time circular dependencies.
Output Format
## Context Health Assessment
### Overall Score: 82/100 (Good)
| Context | Modules | API | Fan-Out | Fan-In | Score |
|---------|---------|-----|---------|--------|-------|
| Accounts | 5 | 12 | 2 | 4 | 95 |
| Orders | 18 | 45 | 8 | 3 | 62 |
| Shared | 2 | 8 | 0 | 12 | 78 |
### Issues Found
1. **Orders** - Too large (18 modules, 45 funcs)
- Consider: Extract Fulfillment, Invoicing sub-contexts
2. **Orders** - High fan-out (8 contexts)
- Consider: Review if all dependencies necessary
### Recommendations
- Split Orders into Orders + Fulfillment
- Review Accounts ← Billing dependency
Iron Laws - Never Violate These
- Controllers call only contexts - No direct Repo access from web layer
- Schemas are pure data - No side effects, no Repo calls in schema modules
- Contexts own their schemas - Don't import schemas from other contexts
- Explicit dependencies only - Cross-context calls must be intentional
- DO NOT refactor context boundaries without running
mix xreffirst — Refactoring without dependency data creates new violations; always map the dependency graph before moving modules
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.
- 6d ago First seen · 138 lines · 35 tokens per session scan A a6bd642aae7b
phx-boundaries is a skill published in the GitHub repository oliver-kriska/claude-elixir-phoenix (542 stars, last pushed 4d ago), licensed MIT. It adds 35 tokens to every session and 1,113 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 91% identical to boundaries, differing in 25 lines, and is treated as a copy.
Other skills, from other repositories
bug-fix
Use when a bug, regression, or unexpected behaviour is reported and the user wants it fixed end to end — "why is X broken", "this stopped working after Y", "fix this crash". Also use when a symptom is known but its cause is not. Not for building new behaviour, and not for a change whose cause is already proven.
bug-investigate
Use when someone wants to know WHY something is broken and has not asked for it to be fixed — "why is this happening", "what's causing this error", "find out what's wrong", "diagnose this before we decide". Also use before committing to a fix, when the cause is unknown and the decision depends on it. Not for fixing …
gurobi-advanced-features
When the user wants to use Gurobi beyond plain model building — callbacks for lazy constraints, user cuts, heuristic solution injection, and early termination; IIS computation for diagnosing an infeasible model; the solution pool; the multi-objective API; the matrix API (addMVar/addMConstr); MIP starts; and parameter…
cige-product-defect-escalation
Invoked by cige-failure-classification when a run is classified as a Product Defect: execution reached the system under test, the environment is healthy, execution steps are current — but the outcome does not match Intent.
cige-stale-execution-repair
Invoked by cige-failure-classification in two situations: Outdated Test Logic (Mode A — repair Execution[]) and a confirmed False Positive (Mode B — strengthen Guardrails). These are different repairs with different targets; do not conflate them.
diagnose
Disciplined diagnosis loop for hard bugs and performance regressions. Reproduce → minimise → hypothesise → instrument → fix → regression-test. Use when user says "diagnose this" / "debug this", reports a bug, says something is broken/throwing/failing, or describes a performance regression.