loop-guardrail 0.1.0

Repetitive execution loop detector for AI agents.
Documentation 
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# loop-guardrail

[![Crates.io](https://img.shields.io/crates/v/loop-guardrail.svg)](https://crates.io/crates/loop-guardrail)
[![docs.rs](https://docs.rs/loop-guardrail/badge.svg)](https://docs.rs/loop-guardrail)
[![License: Apache-2.0](https://img.shields.io/badge/license-Apache--2.0-blue.svg)](LICENSE)

Repetitive execution loop detector for AI agents. Tracks tool-call signatures across a session,
warns when the same call is repeated, and hard-stops when a call has failed too many times in a
row — protecting against runaway tool loops that would otherwise burn tokens and money.

Canonicalizes JSON tool arguments (recursive key sort) so semantically identical calls always
hash to the same signature.

## Installation

```sh
cargo add loop-guardrail
```

## Usage

```rust
use loop_guardrail::{ToolCallGuardrailConfig, ToolCallGuardrailController};
use serde_json::json;

let config = ToolCallGuardrailConfig {
    hard_stop_enabled: true,
    warnings_enabled: true,
    exact_failure_warn_after: 2,
    exact_failure_block_after: 3,
    ..Default::default()
};
let mut ctrl = ToolCallGuardrailController::new(Some(config));

let decision = ctrl.before_call("terminal", Some(&json!({"cmd": "ls"})));
if decision.allows_execution() {
    // run the tool, then report back:
    ctrl.after_call("terminal", Some(&json!({"cmd": "ls"})), Some("err"), Some(true));
}
```

## License

Licensed under the Apache License, Version 2.0. See [LICENSE](LICENSE) for details.