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 rules/jterratsdev/ableton-live-mcp/rule-compositiongit clone --depth 1 https://github.com/jterratsdev/ableton-live-mcpWhat 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 | $0.00389 | $0.00389 |
| Opus 5 | $0.00195 | $0.00195 |
| Sonnet 5 | $0.00078 | $0.00078 |
| Haiku 4.5 | $0.00039 | $0.00039 |
Grade A, and why
rule-composition 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.
What it actually says
Rule Composition
Prefer small, focused rule files referenced from a concise root file. Large monolithic instruction files are harder to maintain, easier to contradict, and waste context on rules that may not apply to the current task.
Root Files
- Root files such as
AGENTS.mdandCLAUDE.mdmust act as entry points, not full manuals. - Keep root files limited to universal rules, role summaries, and pointers to specialized rule files.
- If a section grows beyond a short summary, extract it to
rules/*.mdcand keep only the operating principle in the root file.
Specialized Rules
- Use one rule file per responsibility area: architecture, API design, data modeling, frontend, performance, concurrency, testing, security, delivery, collaboration, infrastructure, DevOps tooling, or product.
- Each rule file must have a clear
descriptionand a single reason to change. - Avoid duplicating detailed guidance across files. Put the source of truth in one rule and summarize it elsewhere.
Skill-Like Loading
- Treat specialized rule files like skills: load the relevant rule only when the task needs that domain.
- For broad delivery work, load roles, collaboration, readiness/done, API design, data modeling, frontend, performance, concurrency, testing, security, delivery quality gates, UX/UI, release/rollback, DevOps tooling, documentation, dependency, config, code review, and AI-assisted development rules together.
- For narrow edits, load the smallest set of rules that can govern the change safely.
Maintenance
- Prefer adding a new focused rule file over expanding an unrelated one.
- Review root files periodically and remove details that have moved into specialized rules.
- If two rules conflict, keep the stricter safety, security, or quality requirement and record the decision.
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 · 29 lines · 389 tokens per session scan A 67d2884208e0
rule-composition is a cursor rule published in the GitHub repository jterratsdev/ableton-live-mcp (0 stars, last pushed 8d ago), licensed MIT. It adds 389 tokens to every session, about $0.0019 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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