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/tyrchen/cursor-rust-rulesWrote 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/rules/tyrchen/cursor-rust-rules/protobuf-grpc)<a href="https://agentmods.dev/rules/tyrchen/cursor-rust-rules/protobuf-grpc"><img src="https://agentmods.dev/badge/rules/tyrchen/cursor-rust-rules/protobuf-grpc/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/rules/tyrchen/cursor-rust-rules/protobuf-grpc"><img src="https://agentmods.dev/badge/rules/tyrchen/cursor-rust-rules/protobuf-grpc.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 | $0.00000 | $0.08430 |
| Opus 5.5 | $0.00000 | $0.03372 |
| Sonnet 5.5 | $0.00000 | $0.01686 |
| Haiku 4.5 | $0.00000 | $0.00843 |
Grade A, and why
protobuf-grpc 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 1mo 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.
How it starts
The opening of the file, as written. The whole thing — 1,214 lines — stays where its author put it; the contents beside it link to each section on GitHub.
🛜 RUST PROTOBUF & GRPC STANDARDS
TL;DR: Modern protobuf and gRPC patterns using prost/tonic 0.13+ with clean code generation, Inner data structures, MessageSanitizer trait, gRPC reflection, and simplified service implementations.
🔍 PROTOBUF & GRPC DESIGN STRATEGY
graph TD
Start["gRPC Service Design"] --> ProtoDesign["Protocol Buffer Design"]
ProtoDesign --> CodeGen["Code Generation"]
CodeGen --> DataStructures["Data Structure Design"]
DataStructures --> InnerTypes["Inner Types Pattern"]
DataStructures --> Sanitization["Message Sanitization"]
InnerTypes --> BusinessLogic["Business Logic Separation"]
Sanitization --> BusinessLogic
BusinessLogic --> ServiceImpl["Service Implementation"]
ServiceImpl --> ErrorHandling["Error Handling"]
ErrorHandling --> Testing["Service Testing"]
Testing --> Reflection["gRPC Reflection"]
Reflection --> Deployment["Service Deployment"]
Deployment --> Monitoring["Monitoring & Observability"]
Monitoring --> Production["Production gRPC Service"]
style Start fill:#4da6ff,stroke:#0066cc,color:white
style InnerTypes fill:#4dbb5f,stroke:#36873f,color:white
style Sanitization fill:#ffa64d,stroke:#cc7a30,color:white
style ServiceImpl fill:#d94dbb,stroke:#a3378a,color:white
🎯 PROTOBUF & GRPC FRAMEWORK REQUIREMENTS
Prost/Tonic Configuration
- Use prost/tonic latest versions - Modern protobuf and gRPC implementation
- Clean code generation - Organized pb module structure with proper imports
- Inner data structures - Simplified, optional-free data structures for business logic
- MessageSanitizer trait - Consistent data transformation patterns
- Simplified service methods - Clean separation between gRPC and business logic
📦 PROTOBUF & GRPC DEPENDENCIES
# Cargo.toml - Protobuf & gRPC dependencies
[dependencies]
# Core protobuf and gRPC
prost = "0.13"
prost-types = "0.13"
tonic = { version = "0.13", features = ["gzip", "tls", "tls-roots", "compression"] }
# Build-time dependencies
[build-dependencies]
prost-build = "0.13"
tonic-build = { version = "0.13", features = ["prost"] }
# Data structures and serialization
serde = { version = "1.0", features = ["derive"] }
serde_json = "1.0"
typed_builder = "0.18"
# Error handling
anyhow = "1.0"
thiserror = "2.0"
# Async runtime
tokio = { version = "1.45", features = ["macros", "rt-multi-thread", "signal"] }
tokio-stream = { version = "0.1", features = ["net"] }
# Logging and tracing
tracing = "0.1"
tracing-subscriber = { version = "0.3", features = ["env-filter", "json"] }
# Optional: Additional features
tower = "0.4" # Middleware
tower-http = { version = "0.5", features = ["trace", "cors"] }
uuid = { version = "1.0", features = ["v4", "serde"] }
chrono = { version = "0.4", features = ["serde"] }
[dev-dependencies]
tonic-health = "0.13" # Health check service
tonic-reflection = "0.13" # gRPC reflection service
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.
- 1mo ago First seen · 1,214 lines · 0 tokens per session scan A 034e4034b866
protobuf-grpc is a cursor rule published in the GitHub repository tyrchen/cursor-rust-rules (27 stars, last pushed 1y ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 8,430 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 2026-08-30.
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