> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/dotandev/hintents/llms.txt
> Use this file to discover all available pages before exploring further.

# erst doctor

> Diagnose development environment setup

Check the status of required dependencies and development tools.

## Usage

```bash theme={null}
erst doctor [flags]
```

## Description

The `doctor` command verifies your development environment is correctly configured for Erst. It checks:

* **Go installation**: Verifies Go is installed and version matches `go.mod`
* **Rust toolchain**: Checks `rustc` and `cargo` are available
* **Simulator binary**: Locates the `erst-sim` executable
* **Config files**: Validates TOML syntax in configuration files
* **RPC endpoint**: Tests connectivity to the configured RPC server

<Info>
  Use this command to troubleshoot installation issues or verify your setup before debugging transactions.
</Info>

## Flags

<ParamField path="--verbose" type="boolean" default="false">
  Show detailed diagnostic information including file paths and version checks

  Alias: `-v`
</ParamField>

## Examples

<CodeGroup>
  ```bash Basic check theme={null}
  erst doctor
  ```

  ```bash Verbose output theme={null}
  erst doctor --verbose
  ```
</CodeGroup>

## Output

The command displays a checklist of dependencies:

```
Erst Environment Diagnostics
=============================

[OK] Go (go1.21.0)
[OK] Rust (rustc 1.75.0)
[OK] Cargo (cargo 1.75.0)
[OK] Simulator Binary (erst-sim) (local build)
[OK] TOML config
[OK] RPC endpoint

[OK] All dependencies are installed and ready!
```

### Status indicators

* `[OK]` - Dependency is installed and working
* `[FAIL]` - Dependency is missing or misconfigured

### Failure hints

When a check fails, the doctor provides fix hints:

```
[FAIL] Go
  → Install Go from https://go.dev/doc/install (requires Go 1.21+)

[FAIL] Simulator Binary (erst-sim)
  → Build the simulator: cd simulator && cargo build --release
```

## Dependency checks

### Go

Verifies:

* Go is in PATH
* Version is installed
* Version matches `go.mod` requirements

**Fix hint**: Install Go from [https://go.dev/doc/install](https://go.dev/doc/install)

### Rust (rustc)

Verifies:

* `rustc` is in PATH
* Version is available

**Fix hint**: Install Rust from [https://rustup.rs/](https://rustup.rs/) or run:

```bash theme={null}
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
```

### Cargo

Verifies:

* `cargo` is in PATH
* Version is available

**Fix hint**: Cargo is included with Rust. Install from [https://rustup.rs/](https://rustup.rs/)

### Simulator Binary (erst-sim)

Verifies:

* Binary exists in standard locations:
  * `simulator/target/release/erst-sim`
  * `./erst-sim`
  * `../simulator/target/release/erst-sim`
  * In system PATH

**Fix hint**: Build the simulator:

```bash theme={null}
cd simulator && cargo build --release
```

### TOML config

Verifies:

* Configuration files (`.erst.toml`, `~/.erst.toml`, `/etc/erst/config.toml`) have valid syntax
* Non-comment lines contain `=` for key-value pairs

**Fix hint**: Fix syntax in `.erst.toml` or remove the malformed file

### RPC endpoint

Verifies:

* Configured RPC endpoint is reachable
* Health check endpoint responds within 5 seconds

**Fix hint**: Set `ERST_RPC_URL` or ensure the default RPC is reachable

## Verbose mode

With `--verbose`, the doctor shows additional information:

```
Erst Environment Diagnostics
=============================

[OK] Go (go1.21.0)
  Path: /usr/local/go/bin/go

[OK] Rust (rustc 1.75.0)
  Path: /Users/dev/.cargo/bin/rustc

[OK] Cargo (cargo 1.75.0)
  Path: /Users/dev/.cargo/bin/cargo

[OK] Simulator Binary (erst-sim) (local build)
  Path: /Users/dev/erst/simulator/target/release/erst-sim

[OK] TOML config
[OK] RPC endpoint

[OK] All dependencies are installed and ready!
```

## Exit codes

* `0` - All checks passed
* `0` - Some checks failed (warnings only, does not exit with error)

## Common issues

### Go version mismatch

**Problem**: `go.mod requests 1.21 but installed 1.20`

**Solution**: Upgrade Go to the required version:

```bash theme={null}
# macOS
brew upgrade go

# Linux
# Download from https://go.dev/dl/
```

### Simulator binary not found

**Problem**: `[FAIL] Simulator Binary (erst-sim)`

**Solution**: Build the Rust simulator:

```bash theme={null}
cd simulator
cargo build --release
```

### RPC endpoint unreachable

**Problem**: `[FAIL] RPC endpoint`

**Solution**: Check network connectivity or configure custom RPC:

```bash theme={null}
export ERST_RPC_URL=https://soroban-testnet.stellar.org
erst doctor
```

### TOML syntax error

**Problem**: `[FAIL] TOML config (line 5 missing '=')`

**Solution**: Fix the syntax error in `.erst.toml`:

```toml theme={null}
# Before (invalid)
rpc_url https://example.com

# After (valid)
rpc_url = "https://example.com"
```

## Related commands

* [debug](/commands/debug) - Main debugging command that uses these dependencies
* [cache](/commands/cache) - Manage cached data (uses RPC endpoint)