ECC is a toolkit that organizes and improves how coding agents work through skills, memory, security checks, research practices, and related extensions. It is for developers using agents such as Claude Code, Codex, OpenCode, and Cursor.
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.
git clone --depth 1 https://github.com/affaan-m/ECCWrote 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/commands/affaan-m/ecc/add-language-rules)<a href="https://agentmods.dev/commands/affaan-m/ecc/add-language-rules"><img src="https://agentmods.dev/badge/commands/affaan-m/ecc/add-language-rules/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/commands/affaan-m/ecc/add-language-rules"><img src="https://agentmods.dev/badge/commands/affaan-m/ecc/add-language-rules.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 | $0.00016 | $0.00265 |
| Opus 5.5 | $0.00006 | $0.00106 |
| Sonnet 5.5 | $0.00003 | $0.00053 |
| Haiku 4.5 | $0.00002 | $0.00026 |
Grade A, and why
add-language-rules 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 16d 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.
Copies of this mod
4 near-identical copies found in the catalogue:
- add-language-rules — 100% identical, 6 lines differ
- add-language-rules — 100% identical, 6 lines differ
- add-language-rules — 100% identical, 6 lines differ
- add-language-rules — 100% identical, 6 lines differ
What it actually says
/add-language-rules
Use this workflow when working on add-language-rules in ECC.
Goal
Adds a new programming language to the rules system, including coding style, hooks, patterns, security, and testing guidelines.
Common Files
rules/*/coding-style.mdrules/*/hooks.mdrules/*/patterns.mdrules/*/security.mdrules/*/testing.md
Suggested Sequence
- Understand the current state and failure mode before editing.
- Make the smallest coherent change that satisfies the workflow goal.
- Run the most relevant verification for touched files.
- Summarize what changed and what still needs review.
Typical Commit Signals
- Create a new directory under rules/{language}/
- Add coding-style.md, hooks.md, patterns.md, security.md, and testing.md files with language-specific content
- Optionally reference or link to related skills
Notes
- Treat this as a scaffold, not a hard-coded script.
- Update the command if the workflow evolves materially.
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.
- 16d ago Changed · -4 tokens per session a5e9ee83392f
- 1mo ago First seen · 39 lines · 20 tokens per session scan A 4186cde51846
add-language-rules is a command published in the GitHub repository affaan-m/ECC (282,704 stars, last pushed 3d ago), licensed MIT. It adds 16 tokens to every session and 265 once invoked, about $0.0001 per session on Opus 5.5. 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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