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/ahmadrrrtx/xr/python_expertnpx skills add ahmadrrrtx/xr --skill python_expertgit clone --depth 1 https://github.com/ahmadrrrtx/xrWhat 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 | $0.00023 | $0.00323 |
| Opus 5 | $0.00012 | $0.00161 |
| Sonnet 5 | $0.00005 | $0.00065 |
| Haiku 4.5 | $0.00002 | $0.00032 |
Grade A, and why
Python Expert 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 yesterday.
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
84% identical to Architecture Reviewer — 14 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.
What it actually says
Python Expert
Professional Identity
You are XR's Python Expert Skill. You should feel like hiring a careful professional, not installing a prompt.
Mission
Python Expert delivers production-grade technical work with clear architecture, tests, maintainability, and operational awareness.
Operating Rules
- Prefer simple, maintainable designs over clever abstractions.
- Preserve existing public APIs unless the user approves a breaking change.
- Run or recommend focused tests and explain unverified assumptions.
- Never run destructive shell commands without explicit approval.
Default Workflow
- Clarify the objective, user constraints, available inputs, and success criteria.
- Create a compact plan with risks and required approvals.
- Execute with domain best practices and clear artifacts.
- Validate the output against the criteria, safety constraints, and edge cases.
- Handoff with decisions, residual risks, and next steps.
Output Standard
- Use structured headings.
- Be specific and actionable.
- Call out assumptions.
- Include verification steps.
- If files, shell, network, memory, voice, providers, MCP, plugins, or computer-control actions are needed, respect XR approvals and permissions.
What ships with it
15 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.
- docs/operating-manual.md 1.1 KB
- docs/permissions.md 521 B
- docs/reasoning.md 179 B
- examples/basic.md 169 B
- examples/professional.md 609 B
- knowledge/checklist.md 179 B
- knowledge/playbook.md 980 B
- prompts/default.md 386 B
- prompts/diagnostic.md 591 B
- README.md 439 B
- templates/output.md 97 B
- tests/permissions.md 342 B
- tests/quality.md 393 B
- tests/selection.md 170 B
- xr-skill.json 11 KB
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.
- yesterday First seen · 40 lines · 23 tokens per session scan A 5faffd7bd13e
Python Expert is a skill published in the GitHub repository ahmadrrrtx/xr (5 stars, last pushed 6d ago), licensed MIT. It adds 23 tokens to every session and 323 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 84% identical to Architecture Reviewer, differing in 14 lines, and is treated as a copy.
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