# `Tinkex.Recovery.Policy`
[🔗](https://github.com/North-Shore-AI/tinkex/blob/v0.4.0/lib/tinkex/recovery/policy.ex#L1)

Configuration for opt-in training run recovery.

Defaults are **disabled** and conservative: three attempts, 5s base backoff
(capped at 60s), 30s polling interval, and optimizer state restore enabled.
The checkpoint strategy defaults to `:latest`; `:best` is reserved for future
support, and `{:specific, path}` targets an explicit checkpoint path.

Telemetry events emitted by the recovery pipeline:

  * `[:tinkex, :recovery, :detected]` - monitor observed `corrupted: true`
  * `[:tinkex, :recovery, :started]` - executor attempt began
  * `[:tinkex, :recovery, :checkpoint_selected]` - checkpoint picked
  * `[:tinkex, :recovery, :client_created]` - training client created
  * `[:tinkex, :recovery, :completed]` - recovery finished successfully
  * `[:tinkex, :recovery, :failed]` - attempt failed (before exhaustion)
  * `[:tinkex, :recovery, :exhausted]` - max attempts reached, no recovery
  * `[:tinkex, :recovery, :poll_error]` - monitor failed to poll run status (keeps state)

# `checkpoint_strategy`

```elixir
@type checkpoint_strategy() :: :latest | :best | {:specific, String.t()}
```

# `failure_callback`

```elixir
@type failure_callback() :: (String.t(), term() -> :ok) | nil
```

# `recovery_callback`

```elixir
@type recovery_callback() ::
  (pid() | nil, pid(), Tinkex.Types.Checkpoint.t() -> :ok) | nil
```

# `t`

```elixir
@type t() :: %Tinkex.Recovery.Policy{
  backoff_ms: pos_integer(),
  checkpoint_strategy: checkpoint_strategy(),
  enabled: boolean(),
  max_attempts: pos_integer(),
  max_backoff_ms: pos_integer(),
  on_failure: failure_callback(),
  on_recovery: recovery_callback(),
  poll_interval_ms: pos_integer(),
  restore_optimizer: boolean()
}
```

# `new`

```elixir
@spec new(t() | keyword() | map() | nil) :: t()
```

Build a recovery policy from a struct, keyword list, or map.

Unknown keys are ignored; invalid values fall back to defaults to keep the
policy conservative and opt-in.

---

*Consult [api-reference.md](api-reference.md) for complete listing*