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packages/foundation/flow/workflow/src/middleware/retry/retry.md

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+# retry
+
+<!-- begin:auto-docs -->
+_(no submodules)_
+<!-- end:auto-docs -->
+
+## Purpose
+
+`withRetry` is the standalone, reusable retry executor that
+`@suaveplan/workflow` exposes alongside the `Step.retry` configuration.
+Where the step's built-in retry is bound to the step's lifecycle (it only
+fires inside `Step.run`), `withRetry` can wrap any async function and is
+intended for the moments callers want retry semantics outside the
+workflow engine — e.g. retrying a manual cleanup, retrying a request
+inside a custom step that doesn't quite fit `Step`, or building higher-level
+retry-with-circuit-breaker compositions.
+
+The module also re-exports the `RetryPresets` object so callers can pick
+sensible defaults (`quick`, `standard`, `aggressive`) without duplicating
+the numbers in every consumer.
+
+## Features
+
+- `withRetry(fn, options?)` — retries with the resolved config.
+- `createRetryWrapper(options?)` — reusable closure capturing options.
+- `resolveRetryConfig(partial?)` — fills in defaults from
+  `constants/index`.
+- `RetryPresets.{none, quick, standard, aggressive}` — pre-baked configs.
+- Hooks: `onRetry(err, attempt)` before each backoff, `shouldRetry(err,
+  attempt)` to short-circuit early.
+
+## Usage: Basic Example
+
+```ts
+import { withRetry, RetryPresets } from "@suaveplan/workflow";
+
+const result = await withRetry(
+	() => fetch("/api/data").then((r) => r.json()),
+	RetryPresets.standard(),
+);
+```
+
+## Usage: Advanced Example
+
+```ts
+import { createRetryWrapper } from "@suaveplan/workflow";
+
+const wrap = createRetryWrapper({
+	maxAttempts: 4,
+	strategy: "exponential",
+	delayMs: 100,
+	maxDelayMs: 2_000,
+	shouldRetry: (err) => !(err instanceof TypeError),
+	onRetry: (err, attempt) => {
+		console.warn(`attempt ${attempt} failed:`, err.message);
+	},
+});
+
+const json = await wrap(() => fetch("/api/v1").then((r) => r.json()));
+```
+
+## API Reference
+
+- `RetryOptions extends Partial<RetryConfig>` —
+  - `shouldRetry?: (error, attempt) => boolean`
+  - `onRetry?: (error, attempt) => void`
+- `resolveRetryConfig(options?: Partial<RetryConfig>): RetryConfig`.
+- `withRetry<T>(fn: () => T | Promise<T>, options?: RetryOptions): Promise<T>`.
+- `createRetryWrapper(options?: RetryOptions): <T>(fn) => Promise<T>`.
+- `RetryPresets` — `{ none, quick, standard, aggressive }`, each a function
+  returning a fresh `RetryConfig`.
+
+## Implementation Notes
+
+`withRetry` always rethrows the *last* error, not the *first*. Callers
+that want the first-error semantics can capture it inside an `onRetry`
+closure. The loop checks `attempt >= maxAttempts` before `shouldRetry` so
+the final attempt always actually runs even if `shouldRetry` would have
+returned false — the contract is "make all the attempts you promised."
+
+`RetryPresets` are factory functions rather than constants so each call
+returns a fresh object. That keeps callers from accidentally mutating a
+shared preset (e.g. by spreading-and-overriding) and seeing the change
+ripple through the rest of the application.