rust-conventions

A set of Rust coding rules for this project, including error handling, deterministic output, defensive input parsing, and keeping reading and writing formats compatible.

In plain words
What is it for?
Implementing Rust features, parsing user settings, generating files, maintaining adapter round trips, and checking changes with tests and Clippy.
Why use it?
It prevents common inconsistencies and unsafe assumptions when changing Rust code or generated configuration files.

Cursor rule for Cursor

Install

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.

agentmods
npx agentmods add rules/maxgfr/conforme/rust-conventions
Clone the repo
git clone --depth 1 https://github.com/maxgfr/conforme

Made for: Cursor.

Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 204 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.00204
Opus 5 $0.00000 $0.00102
Sonnet 5 $0.00000 $0.00041
Haiku 4.5 $0.00000 $0.00020

Measured yesterday against content hash 7d80223be3a3, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

rust-conventions 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.

.cursor/rules/rust-conventions.mdc · 14 lines

What it actually says

  • Run cargo clippy -- -D warnings before considering any change complete
  • Run cargo test after modifying adapter logic, MCP generation, or skills generation
  • Use anyhow::Result for fallible functions, anyhow::Context for error messages
  • Use BTreeMap (not HashMap) for deterministic output ordering in generated files
  • Parse frontmatter fields defensively: use .and_then(|v| v.as_str()) chains, never .unwrap() on user input
  • When parsing tool-separated lists (e.g. allowed-tools, tools), handle both space-separated AND comma-separated formats: split_whitespace().flat_map(|t| t.split(','))
  • Keep adapter read() and generate() symmetric: if generate() writes a field, read() must parse it back correctly (round-trip guarantee)
Changes

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.

  1. yesterday First seen · 14 lines · 0 tokens per session scan A 7d80223be3a3

Subscribe to this mod's changes

rust-conventions is a cursor rule published in the GitHub repository maxgfr/conforme (2 stars, last pushed 7d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 204 tokens. 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.