# π Agenterra: Model Context Protocol Generator
**Generate production-ready MCP (Model Context Protocol) servers and clients from OpenAPI specs with minimal configuration.**
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[](https://github.com/clafollett/agenterra/releases)
[](https://www.rust-lang.org/)
[](LICENSE)
[](https://www.openapis.org/)
---
**Agenterra** transforms your OpenAPI specifications into fully-functional MCP servers and clients with type-safe Rust code, ready for integration with AI tools and workflows. Perfect for:
- **AI/ML Engineers** π€ - Quickly expose APIs for LLM tool use
- **API Developers** π οΈ - Generate production-ready MCP servers from existing OpenAPI specs
- **FinTech & Data Teams** π - Build compliant financial data APIs with built-in validation
- **Startups & Enterprises** π - Accelerate development of AI-powered applications
## β¨ Features
- **β‘ Blazing Fast** - Built with Rust for maximum performance and safety
- **π OpenAPI 3.0+ Support** - Seamless integration with existing API specifications
- **π¦ Type-Safe Rust** - Generate idiomatic, production-ready Rust code
- **π¨ Template-Based** - Customize every aspect with Tera templates
- **π Built-in Validation** - Automatic OpenAPI schema validation
- **π Production Ready** - Includes logging, error handling, and configuration out of the box
- **π MCP Protocol Support** - Full compatibility with Model Context Protocol
- **πΎ SQLite Resource Caching** - Built-in resource caching with connection pooling for MCP clients
- **π¦ Binary Distribution** - Easy installation and deployment
## π Quick Start
### Prerequisites
- [Rust 1.86.0+](https://rustup.rs/)
### Method 1: Build & Run from Source
```bash
# Clone the repository
git clone https://github.com/clafollett/agenterra.git
cd agenterra
# Generate MCP server from a local file without install:
cargo run -- scaffold mcp server --schema-path ./tests/fixtures/openapi/petstore.openapi.v3.json --output-dir .agenterra/cargo_run_petstore_mcp_server_local_file --base-url https://petstore3.swagger.io
# Generate MCP server from a remote URL without install:
cargo run -- scaffold mcp server --schema-path https://petstore3.swagger.io/api/v3/openapi.json --output-dir .agenterra/cargo_run_petstore_mcp_server_remote_url
# Generate MCP client without install:
cargo run -- scaffold mcp client --project-name petstore-client --output-dir .agenterra/cargo_run_petstore_mcp_client
# Or install the CLI
cargo install --path .
# Generate your MCP server from a local file
agenterra scaffold mcp server --schema-path ./tests/fixtures/openapi/petstore.openapi.v3.json --output-dir .agenterra/installed_petstore_mcp_server_local_file --base-url https://petstore3.swagger.io
# Generate MCP server from a remote URL
agenterra scaffold mcp server --schema-path https://petstore3.swagger.io/api/v3/openapi.json --output-dir .agenterra/installed_petstore_mcp_server_remote_url
# Generate MCP client
agenterra scaffold mcp client --project-name petstore-client --output-dir .agenterra/installed_petstore_mcp_client
```
> **Note:** After the single-crate refactor, you can now install directly from the project root with `cargo install --path .`
### Method 2: Install from Git
```bash
# Install latest version
cargo install --git https://github.com/clafollett/agenterra.git agenterra
# Install specific version. Example: v0.1.0
cargo install --git https://github.com/clafollett/agenterra.git --tag v<VERSION> agenterra
```
### Method 3: From Pre-built Binary (Coming soon)
1. Download the latest release for your platform from [Releases](https://github.com/clafollett/agenterra/releases)
2. Make it executable and run:
```bash
chmod +x agenterra
./agenterra scaffold mcp server --schema-path ./tests/fixtures/openapi/petstore.openapi.v3.json --output-dir .agenterra/installed_petstore_mcp_server_local_file --base-url https://petstore3.swagger.io
./agenterra scaffold mcp server --schema-path https://petstore3.swagger.io/api/v3/openapi.json --output-dir .agenterra/installed_petstore_mcp_server_remote_url
./agenterra scaffold mcp client --project-name petstore-client --output-dir .agenterra/installed_petstore_mcp_client
```
## π Integrating with MCP Clients
### VS Code Integration
Add this to your VS Code settings (File > Preferences > Settings > Open Settings JSON):
```json
{
"mcp": {
"servers": {
"petstore": {
"command": "cargo",
"args": ["run", "--manifest-path", "/path/to/petstore-server/Cargo.toml"]
}
}
}
}
```
### Cursor Integration
Add this to your Cursor settings (File > Preferences > Settings > Extensions > MCP):
```json
{
"mcpServers": {
"petstore": {
"command": "cargo",
"args": ["run", "--manifest-path", "/path/to/petstore-server/Cargo.toml"]
}
}
}
```
### π΅οΈββοΈ Testing with MCP Inspector
Test your MCP server with the MCP Inspector:
```bash
# Run directly with npx
npx @modelcontextprotocol/inspector cargo run --manifest-path=/path/to/petstore-server/Cargo.toml
# Or install globally
npm install -g @modelcontextprotocol/inspector
modelcontextprotocol-inspector cargo run --manifest-path=/path/to/petstore-server/Cargo.toml
```
## β‘ Best Practices
Agenterra is designed to scaffold a well-structured MCP servers from OpenAPI specs. This is a great starting point, not necessarily a `Best Practice`. Wrapping an OpenAPI spec under an MCP facade is convenient, but not always the βproperβ way to build MCPs. For robust, agent-friendly tools, consider how your server can best expose business logic, aggregate data, and provide clear, useful tool contracts.
**Considerations:**
- Treat the generated code as a foundation to extend and customize.
- Don't assume a 1:1 mapping of OpenAPI endpoints to MCP tools is ideal; you may want to aggregate multiple API calls into a single tool, or refactor handlers for advanced logic.
- Use the scaffold to rapidly stub out endpoints, then iterate and enhance as needed.
---
## π€ Why Agenterra?
Postman now offers robust support for the Model Context Protocol (MCP), including:
- MCP client and server features
- Code generation
- A catalog of hosted, discoverable MCP endpoints
- Visual agent-building and cloud collaboration
**When should you use Agenterra?**
- **Offline, air-gapped, or regulated environments** where cloud-based tools arenβt an option
- **Rust-first, codegen-centric workflows:** Generate type-safe, production-grade Rust MCP servers from OpenAPI specs, ready for CI/CD and self-hosting
- **Full template control:** Tweak every line of generated code, use custom templates, and integrate with your own infra
- **CLI-first automation:** Perfect for embedding in build scripts and automated workflows
**When should you use Postman?**
- Visual design, rapid prototyping, and cloud collaboration
- Building, testing, and deploying MCP agents with a GUI
- Discovering and consuming public MCP endpoints
**Summary:**
- Use Postman for visual, collaborative, and cloud-first agent development
- Use Agenterra for local, reproducible, code-first MCP server generation with maximum control and zero cloud dependencies
---
## ποΈ Architecture
Agenterra is built for extensibility, automation, and code quality. Hereβs how the core pieces fit together:
**Core Modules:**
- `openapi`: Loads and validates OpenAPI specs (YAML/JSON, local or URL)
- `generator`: Orchestrates code generation from the parsed OpenAPI model
- `template`: Handles Tera-based templates for idiomatic Rust code
- `cli`: Command-line interface for scaffolding, configuration, and workflow
**Code Generation Flow:**
```
OpenAPI Spec (local file or URL)
β
βΌ
[openapi module]
β
βΌ
[generator module]
β
βΌ
[template module]
β
βΌ
Generated Rust MCP Server (Axum, etc.)
```
- The generated server uses [Stdio](https://modelcontextprotocol.io/introduction) as the primary MCP protocol for agent integration, but can be extended for HTTP/SSE and other transports.
- All code is idiomatic Rust, ready for further customization and production deployment.
## πΎ Resource Caching
Generated MCP clients include a sophisticated SQLite-powered resource caching system:
**Features:**
- **Connection Pooling** - r2d2 connection pool for concurrent access
- **Character Encoding** - Automatic charset detection from HTTP headers
- **TTL Support** - Configurable time-to-live for cache entries
- **Analytics** - Built-in cache hit/miss tracking and performance metrics
- **ACID Transactions** - Database integrity with rollback support
- **Auto-cleanup** - Configurable expired resource cleanup
**Configuration Options:**
```rust
let config = CacheConfig {
database_path: "cache.db".to_string(),
default_ttl: Duration::from_secs(3600),
max_size_mb: 100,
pool_max_connections: Some(10),
pool_max_lifetime: Some(Duration::from_secs(300)),
auto_cleanup: true,
..Default::default()
};
```
---
## π€ Contributing
We welcome contributions from the community! To keep Agenterra high-quality and maintainable, please follow these guidelines:
- **Fork & Clone**: Fork the repo and clone your fork locally.
- **Branch Naming**: Use the convention `<type>/issue-<number>/<description>` (e.g., `docs/issue-57/update-readme`).
- **Pull Requests**:
- All PRs require review.
- All tests must pass (`cargo test` and integration tests).
- Code coverage must not decrease.
- Update documentation for any user-facing or API changes.
- **Testing**:
- Add or update unit and integration tests for all new features or bugfixes.
- Run: `cargo test --test e2e_mcp_test`
- **Docs**:
- Update relevant docs and add examples for new features.
- Document any new patterns or conventions.
- **CI/CD**:
- Ensure your branch passes all checks before requesting review.
For more details, see [CONTRIBUTING.md](CONTRIBUTING.md) if available.
---
## π οΈ Developer Workflow
Hereβs how to work productively with Agenterra as a contributor or advanced user:
### π§ͺ Running Tests
- **Unit & Integration Tests:**
- Run all tests: `cargo test`
- Run integration tests (all templates with OpenAPI specs):
```bash
cargo test --test e2e_mcp_test
```
- **Test Location:** See [`tests/e2e_mcp_test.rs`](tests/e2e_mcp_test.rs) for integration coverage.
- **Test-First Principle:** Add failing tests before implementing new features or bugfixes.
### ποΈ Building
- **Standard build:**
```bash
cargo build --release
```
### π§© Custom Templates
- See [`docs/TEMPLATES.md`](docs/TEMPLATES.md) for template development
- Add templates under `templates/` directory
---
## ποΈ Generated Project Structure
```
petstore-server/
βββ Cargo.toml # Rust project manifest
βββ src/
β βββ mcp/ # MCP protocol implementation
β β βββ mod.rs # MCP server implementation
β β βββ handlers/ # MCP request handlers
β βββ api/ # Generated API code
β β βββ mod.rs # API module exports
β β βββ models/ # Generated data models
β β βββ operations/ # API operation handlers
β βββ config.rs # Server configuration
β βββ error.rs # Error handling
β βββ main.rs # MCP server entry point
βββ .env # Environment variables
βββ README.md # Project documentation
```
---
## π Examples & Configuration
### Basic Example: Petstore API
```bash
# Download the Petstore OpenAPI spec
curl -o petstore.json https://petstore3.swagger.io/api/v3/openapi.json
# Generate the MCP server
agenterra scaffold mcp server --schema-path petstore.json --output-dir petstore-server
# Generate the MCP client
agenterra scaffold mcp client --project-name petstore-client --output-dir petstore-client
# Build and run the server
cd petstore-server
cargo run
```
### Configuration Options
Agenterra can be configured through:
1. **Command-line arguments** (recommended)
```bash
agenterra scaffold mcp server --schema-path your_api_openapi_spec.json --output-dir my_server
agenterra scaffold mcp client --project-name my-client --output-dir my_client
```
2. **Configuration file** (`agenterra.toml` in project root)
```toml
[scaffold]
schema_path = "your_api_openapi_spec.json"
output_dir = "my_server"
protocol = "mcp"
role = "server"
template = "rust_axum"
```
### Templates
Agenterra uses [Tera](https://tera.netlify.app/) templates for code generation.
**Built-in Server Templates:**
- `rust_axum` - Rust MCP server using Axum web framework
**Built-in Client Templates:**
- `rust_reqwest` - Rust MCP client with REPL interface and SQLite resource caching
**Custom Templates:**
- Create templates under `templates/mcp/server/` or `templates/mcp/client/`
- **Details**: See [`docs/TEMPLATES.md`](docs/TEMPLATES.md)
## π License
MIT License - see [LICENSE](LICENSE) for details.
## π Related Projects
- [MCP Protocol](https://github.com/windsurf-eng/mcp) - Model Context Protocol specification
- [RMCP](https://github.com/windsurf-eng/rmcp) - Rust MCP implementation
- [Axum](https://github.com/tokio-rs/axum) - Web framework for Rust
- [Tera](https://tera.netlify.app/) - Template engine for Rust