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/markmhendrickson/foundation/file_naminggit clone --depth 1 https://github.com/markmhendrickson/foundationWhat 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 | $0.00027 | $0.00330 |
| Opus 5 | $0.00014 | $0.00165 |
| Sonnet 5 | $0.00005 | $0.00066 |
| Haiku 4.5 | $0.00003 | $0.00033 |
Grade A, and why
file_naming 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
File and Folder Naming Convention
All filenames and folder names must use underscores (snake_case), not kebab-case (dashes).
Format
Files:
- Correct:
create_feature_unit.md,setup_cursor_copies.md,run_feature_workflow.md - Incorrect:
create-feature-unit.md,setup-cursor-copies.md,run-feature-workflow.md
Folders:
- Correct:
cursor_rules/,feature_units/,agent_instructions/,repo_adapters/ - Incorrect:
cursor-rules/,feature-units/,agent-instructions/,repo-adapters/(use underscores:cursor_rules/,feature_units/,agent_instructions/,repo_adapters/)
When Creating or Renaming
- Use underscores (snake_case) for all filenames and folder names
- Use underscores when referencing files or folders in documentation
- Symlinks automatically use
foundation_prefix (e.g.,foundation_create_feature_unit.md)
Migration
If existing files or folders use kebab-case:
- Rename from
command-name.mdtocommand_name.mdorfolder-name/tofolder_name/ - Update references in
foundation_config.yaml, documentation files, and scripts - Run
setup_cursor_rules.shto update symlinks
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 · 32 lines · 27 tokens per session scan A db251f285187
file_naming is a cursor rule published in the GitHub repository markmhendrickson/foundation (2 stars, last pushed 1mo ago), licensed MIT. It adds 27 tokens to every session and 330 once invoked, about $0.0001 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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