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/module-boundariesgit 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 | $0.00623 | $0.00623 |
| Opus 5 | $0.00311 | $0.00311 |
| Sonnet 5 | $0.00125 | $0.00125 |
| Haiku 4.5 | $0.00062 | $0.00062 |
Grade A, and why
module-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 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.
How it starts
The opening of the file, as written. The whole thing — 72 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Module Boundaries
Every code change must preserve clear ownership boundaries. Before adding code to an existing file, check whether the file is already large, multi-purpose, or adapter-shaped. If the change would make the file harder to review, create or reuse the correct domain, model, service, repository, or adapter module instead.
Pre-Write Check
- Inspect the target file's current responsibility, exported surface, and size before editing.
- Treat files over 300 lines, functions over 30 lines, and command/controller files with business logic as god-file risk.
- A large existing file is not a reason to keep adding to it. If the new change is separable, extract the new behavior into a focused module and wire it from the existing entry point.
- If extraction is unsafe in the current task, record a follow-up debt task with the reason, affected file, and proposed boundary.
Expected Layers
modelortypes: narrow public data contracts, discriminated unions, schemas, and DTOs.domain: pure invariants, policy decisions, validation rules, state transitions, and calculations.serviceoruse-case: orchestration of domain logic, repositories, clients, and side effects for one workflow.repository,store, orgateway: persistence, file I/O, network I/O, and external system adapters.commands: CLI adapter only. Parse arguments, call services, format output, and convert errors to user-safe messages.weborapi: HTTP/UI adapter only. Parse requests, call services, serialize responses, and map errors.
Logicless Commands
Command modules must remain nearly logicless. They may:
- parse flags and positional arguments;
- choose output format;
- call one service/use-case function;
- map expected errors to CLI messages and exit codes.
Command modules must not:
- own business rules or workflow policy;
- perform direct persistence when a repository/service should own it;
- contain repeated hardcoded registries, option lists, status sets, or provider matrices;
- implement complex loops, joins, retries, or batching;
- become the primary test target for domain behavior.
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 · 72 lines · 623 tokens per session scan A f39eeb5e20d6
module-boundaries is a cursor rule published in the GitHub repository jterratsdev/ableton-live-mcp (0 stars, last pushed 8d ago), licensed MIT. It adds 623 tokens to every session, about $0.0031 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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