Crate car_engine 

Core runtime engine for Common Agent Runtime.

The runtime loop:

1. Receive a proposal (batch of actions from a model)
2. Build a DAG from state_dependencies
3. Execute each level (concurrent if no ABORT actions, sequential otherwise)
4. Validate, execute with idempotency + timeout + retry, commit
5. On abort: rollback state to pre-proposal snapshot

Re-exports

pub use cache::ResultCache;

pub use capabilities::CapabilitySet;

pub use checkpoint::Checkpoint;

pub use rate_limit::RateLimit;

pub use rate_limit::RateLimiter;

Modules

cache

Cross-proposal result cache for tool call results.

capabilities

Per-agent capability permissions for the Common Agent Runtime.

checkpoint

Checkpoint and resume support for the Common Agent Runtime.

rate_limit

Token bucket rate limiter for tool calls with backpressure support.

Structs

CostBudget

Budget constraints for proposal execution.

Runtime

Common Agent Runtime — deterministic execution layer.

Traits

ToolExecutor

Trait for tool execution. Implement this to provide tools to the runtime.

Functions

format_tool_result

Format a tool result for feeding back to a model.