diff --git a/ARCHITECTURE.md b/ARCHITECTURE.md
index f95d04a..cfcd857 100755
--- a/ARCHITECTURE.md
+++ b/ARCHITECTURE.md
@@ -171,6 +171,10 @@ prautoblogger/
 │   │   ├── class-open-router-image-pricing.php   # Model resolution + per-image cost estimation
 │   │   ├── class-open-router-config.php          # API base URL (direct vs AI Gateway)
 │   │   ├── class-open-router-request-builder.php # Header building + Hostinger cURL auth workaround
+│   │   ├── class-runware-image-provider.php     # Runware FLUX.1 (default v0.9.0+)
+│   │   ├── class-runware-image-pricing.php      # FLUX schnell/dev cost table + resolver
+│   │   ├── class-runware-image-support.php      # Key, response parsing, retry, dimension snap
+│   │   ├── class-runware-image-batch.php        # True parallel curl_multi batch dispatcher
 │   │   ├── class-cloudflare-image-provider.php   # Cloudflare Workers AI (sequential batch fallback)
 │   │   ├── class-cloudflare-image-pricing.php    # Model alias + per-MP cost estimation
 │   │   ├── class-cloudflare-image-validator.php  # Non-destructive credential + connectivity check
@@ -479,6 +483,7 @@ Stored on every PRAutoBlogger-generated post:
 | Reddit .json | Fallback for posts + only source for comments | None (unauthenticated) | ~10 req/min (datacenter IPs often blocked) | `providers/class-reddit-json-client.php` |
 | Google Analytics 4 | Post performance metrics | OAuth2 service account | Standard GA4 limits | `core/class-ga4-client.php`, `core/class-metrics-collector.php` |
 | Cloudflare Workers AI | Image generation (FLUX.1 schnell / dev) for article hero, thumbnail, and IG placements | API token (encrypted in wp_options) + account ID | Workers AI per-account quotas | `providers/class-cloudflare-image-provider.php`, `providers/class-cloudflare-image-pricing.php`, `providers/class-cloudflare-image-validator.php` |
+| Runware (FLUX.1 via runware.ai) | **Default** image backend (v0.9.0+): schnell ~$0.0006/image, dev ~$0.02/image. True parallel generation via curl_multi. | API key (encrypted in wp_options) | Account-level quotas | `providers/class-runware-image-provider.php`, `providers/class-runware-image-pricing.php`, `providers/class-runware-image-support.php`, `providers/class-runware-image-batch.php` |
 
 ---
 
@@ -533,6 +538,10 @@ Reddit rejected our OAuth API application (April 2026). We initially switched to
 
 The admin model picker (v1) needs to list OpenRouter models with pricing and capabilities. We fetch `https://openrouter.ai/api/v1/models` (free, unauthenticated) once daily and store the normalized payload in a WP option fronted by a 24h transient. On stale-and-fetch-fails, we serve last-good + surface a warning. The registry class (`class-open-router-model-registry.php`) takes all config via constructor (option name, transient name, endpoint URL) — no PRAUTOBLOGGER_* constants inside the class body. Phase 2 lifts it into a shared Composer package with zero internal edits. Phase 3 adds a parallel `Cloudflare_WorkersAI_Model_Registry` behind the same interface. Capability vocabulary: `text→text`, `text+image→text`, `text+audio→text`, `text→image`, `text→audio`, `text→video`, `text→embedding`. Cost: $0/month.
 
+### #17: Runware as default image backend (v0.9.0, Apr 2026)
+
+After a comic-style A/B round in Apr 2026, FLUX.1 schnell via Runware was chosen as the default image backend. Cost is ~$0.0006/image vs ~$0.039/image for Gemini 2.5 Flash Image via OpenRouter (≈65× cheaper), and the looser schnell fidelity reads as editorial-cartoon style — a feature, not a bug, for our single-panel comic aesthetic. FLUX.1 dev (~$0.02/image, 28 steps) remains available as an opt-in for higher-fidelity runs. The Runware layer mirrors the OpenRouter split (interface + provider + support + pricing + batch), all under the 300-line cap. The batch class dispatches `imageInference` POSTs via `curl_multi_init/exec/select` — wall-clock time for the A/B pair drops to ≈ the slowest single image. A v0.9.0 one-time migration (`prautoblogger_migrated_default_image_v090`) flips sites still on the legacy default; explicit user selections are preserved. Cloudflare Workers AI remains as a legacy fallback in the registry.
+
 ### #16: Image generation via Cloudflare Workers AI (FLUX.1), via AI Gateway (v0.8.2+)
 The image-generation layer uses FLUX.1 [schnell] on Cloudflare Workers AI as its default model, chosen for its ~$0.0011/MP cost and 2–3 sec latency. FLUX.1 [dev] is a ~4× cost upgrade exposed as a dropdown for specific posts that warrant it. **v0.8.2+**: calls route through the Cloudflare AI Gateway (same gateway we already use for OpenRouter — `gateway.ai.cloudflare.com/v1/{account}/{gateway}/workers-ai/@cf/black-forest-labs/...`) for response caching, unified cost/latency telemetry, and rate limiting. The 2026-04-15 regression that caused the gateway route to 403 on Workers AI has been resolved upstream; verified by direct probe on 2026-04-21. A `prautoblogger_cf_image_via_gateway` toggle (default on) falls back to the direct `api.cloudflare.com/client/v4/accounts/{id}/ai/run/...` URL if the gateway regresses again. The provider lives behind `PRAutoBlogger_Image_Provider_Interface`, so switching to a different image API (DALL-E, Replicate) is a new class implementation plus a one-line swap in the pipeline wiring.
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
index c45daaf..9d61f6a 100755
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,60 @@ All notable changes to PRAutoBlogger will be documented in this file.
 Format follows [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project uses [Semantic Versioning](https://semver.org/).
 
+## [0.9.0] — 2026-04-21
+
+### Added
+
+- **Runware (FLUX.1 schnell) as the default image provider.** New
+  provider at `includes/providers/class-runware-image-*` generates
+  ~$0.0006/image on FLUX.1 schnell (`runware:100@1`) — roughly 65× cheaper
+  than the previous default (Gemini 2.5 Flash Image via OpenRouter at
+  ~$0.039/image). FLUX.1 dev (`runware:101@1`, ~$0.02/image) is also
+  available for higher-fidelity runs. The provider mirrors the
+  OpenRouter split: interface + provider + support + pricing + batch,
+  all under the 300-line cap.
+- **True parallel image generation.** `PRAutoBlogger_Runware_Image_Batch`
+  uses `curl_multi_init/exec/select` to fire all imageInference POSTs
+  concurrently, then downloads the signed URLs concurrently. Wall-clock
+  for the A/B pair drops to ≈ the slowest single image instead of the
+  sum of both.
+- **v0.9.0 one-time migration.** Sites where the image model is empty
+  or still pinned to `google/gemini-2.5-flash-image` are auto-flipped
+  to `runware:100@1` on upgrade, with the provider re-derived from the
+  registry. Flag: `prautoblogger_migrated_default_image_v090`. The
+  Runware API key option (`prautoblogger_runware_api_key`) was added
+  to the `enc:`-prefix migration list so Settings writes go through
+  the same encryption-at-rest path as the other provider keys.
+
+### Changed
+
+- **Image prompt builder steered away from abstract/chemical subjects.**
+  The rewriter system prompt now explicitly refuses to personify
+  molecules, peptides, hormones, or proteins — FLUX (and most diffusion
+  image models) render "anthropomorphic peptide" as an incoherent blob.
+  Default scene guidance is now "concrete, human-scale scenes: people
+  reacting to things, doctors and patients, gym bros with vials, etc."
+  Style suffix unchanged — single-panel comic aesthetic preserved. See
+  `includes/core/class-image-prompt-builder.php::REWRITER_SYSTEM_PROMPT`.
+- **Default image model flipped to `runware:100@1` (FLUX.1 schnell).**
+  `PRAUTOBLOGGER_DEFAULT_IMAGE_PROVIDER` and
+  `PRAUTOBLOGGER_DEFAULT_IMAGE_MODEL` constants in `prautoblogger.php`
+  updated. Cloudflare flux-1-schnell remains in the registry as a legacy
+  fallback for any operators who set it explicitly. Rationale:
+  `image-style` memory (2026-04-21) — schnell passed the comic A/B
+  round and the cost delta funds more generations for the same monthly
+  budget.
+
+### Cost impact
+
+At 50 articles/day × 2 image A/B = 100 images/day:
+
+- Before (Gemini 2.5 Flash Image via OpenRouter): ≈ $3.90/day, ≈ $117/mo
+- After (FLUX.1 schnell via Runware):             ≈ $0.06/day, ≈ $1.80/mo
+
+Net saving: ~$115/mo at current traffic, funded by a single provider
+swap with no user-visible change in article quality.
+
 ## [0.8.2] — 2026-04-21
 
 ### Fixed
diff --git a/includes/admin/class-admin-page.php b/includes/admin/class-admin-page.php
index f954999..a0ed97f 100755
--- a/includes/admin/class-admin-page.php
+++ b/includes/admin/class-admin-page.php
@@ -231,7 +231,7 @@ class PRAutoBlogger_Admin_Page {
 			$option_name = substr( $filter, strlen( 'sanitize_option_' ) );
 		}
 
-		$encrypted = [ 'prautoblogger_openrouter_api_key', 'prautoblogger_ga4_credentials_json', 'prautoblogger_cloudflare_ai_token' ];
+		$encrypted = [ 'prautoblogger_openrouter_api_key', 'prautoblogger_ga4_credentials_json', 'prautoblogger_cloudflare_ai_token', 'prautoblogger_runware_api_key' ];
 		if ( in_array( $option_name, $encrypted, true ) ) {
 			// Empty value means password field wasn't touched — keep existing.
 			if ( '' === $value ) {
diff --git a/includes/admin/class-image-model-registry.php b/includes/admin/class-image-model-registry.php
index cd37bd8..9fd35c6 100644
--- a/includes/admin/class-image-model-registry.php
+++ b/includes/admin/class-image-model-registry.php
@@ -6,12 +6,13 @@ declare(strict_types=1);
  *
  * What: Returns a hardcoded list of image models for the admin model picker.
  *       No API discovery — updated manually when providers add/remove models.
- * Who calls it: PRAutoBlogger_Admin_Page (model picker UI) and
- *               PRAutoBlogger_Image_Pipeline (model validation).
+ * Who calls it: PRAutoBlogger_Admin_Page (model picker UI + save-time provider
+ *               derivation) and PRAutoBlogger_Image_Pipeline (provider lookup).
  * Dependencies: None.
  *
  * @see admin/class-settings-fields-extended.php — Image settings reference this registry.
- * @see core/class-image-pipeline.php            — Validates selected model against this list.
+ * @see core/class-image-pipeline.php            — Derives provider from picked model.
+ * @see providers/class-runware-image-provider.php — Runware FLUX backend.
  */
 class PRAutoBlogger_Image_Model_Registry {
 
@@ -21,22 +22,41 @@ class PRAutoBlogger_Image_Model_Registry {
 	 * Each entry contains:
 	 * - id:             Model identifier used in API calls.
 	 * - name:           Human-readable display name.
-	 * - provider:       'openrouter' or 'cloudflare'.
+	 * - provider:       'runware' | 'openrouter' | 'cloudflare'.
 	 * - cost_per_image: Estimated USD cost per generation.
 	 * - capabilities:   Array of capability tags.
 	 * - description:    Short description for the admin UI.
 	 *
+	 * Ordered cheapest-to-most-expensive within each provider, with the
+	 * recommended default (Runware schnell) at the top.
+	 *
 	 * @return array<int, array<string, mixed>>
 	 */
 	public static function get_models(): array {
 		return [
+			[
+				'id'             => 'runware:100@1',
+				'name'           => 'FLUX.1 schnell (Runware)',
+				'provider'       => 'runware',
+				'cost_per_image' => 0.0006,
+				'capabilities'   => [ 'image_generation' ],
+				'description'    => __( 'Default. Fast, very cheap, comic-friendly fidelity.', 'prautoblogger' ),
+			],
+			[
+				'id'             => 'runware:101@1',
+				'name'           => 'FLUX.1 dev (Runware)',
+				'provider'       => 'runware',
+				'cost_per_image' => 0.02,
+				'capabilities'   => [ 'image_generation' ],
+				'description'    => __( 'Higher fidelity FLUX. ~30x schnell cost.', 'prautoblogger' ),
+			],
 			[
 				'id'             => 'google/gemini-2.5-flash-image',
 				'name'           => 'Gemini 2.5 Flash Image (Nano Banana)',
 				'provider'       => 'openrouter',
 				'cost_per_image' => 0.005,
 				'capabilities'   => [ 'image_generation' ],
-				'description'    => __( 'Good quality, low cost. Recommended.', 'prautoblogger' ),
+				'description'    => __( 'Mid-tier quality, proven.', 'prautoblogger' ),
 			],
 			[
 				'id'             => 'google/gemini-3.1-flash-image-preview',
@@ -76,7 +96,7 @@ class PRAutoBlogger_Image_Model_Registry {
 				'provider'       => 'cloudflare',
 				'cost_per_image' => 0.0007,
 				'capabilities'   => [ 'image_generation' ],
-				'description'    => __( 'Cheapest. Low quality, 4-step.', 'prautoblogger' ),
+				'description'    => __( 'Legacy Cloudflare fallback. Use Runware FLUX instead.', 'prautoblogger' ),
 			],
 		];
 	}
@@ -86,7 +106,7 @@ class PRAutoBlogger_Image_Model_Registry {
 	 * model id is not in the registry.
 	 *
 	 * @param string $model_id Model slug from the admin UI.
-	 * @return string Provider id ('openrouter' | 'cloudflare' | '').
+	 * @return string Provider id ('runware' | 'openrouter' | 'cloudflare' | '').
 	 */
 	public static function provider_for( string $model_id ): string {
 		foreach ( self::get_models() as $model ) {
diff --git a/includes/admin/class-settings-fields-extended.php b/includes/admin/class-settings-fields-extended.php
index 6b30235..f4bfcd0 100644
--- a/includes/admin/class-settings-fields-extended.php
+++ b/includes/admin/class-settings-fields-extended.php
@@ -240,6 +240,14 @@ class PRAutoBlogger_Settings_Fields_Extended {
 				'default'     => '',
 				'description' => __( 'Only needed if using Cloudflare provider.', 'prautoblogger' ),
 			],
+			[
+				'id'          => 'prautoblogger_runware_api_key',
+				'label'       => __( 'Runware API Key', 'prautoblogger' ),
+				'type'        => 'password',
+				'section'     => 'prautoblogger_images',
+				'description' => __( 'Required when using a Runware FLUX model. Get your key at runware.ai/signup.', 'prautoblogger' ),
+				'icon'        => '🔑',
+			],
 			[
 				'id'          => 'prautoblogger_image_style_suffix',
 				'label'       => __( 'Style Suffix', 'prautoblogger' ),
diff --git a/includes/class-activator.php b/includes/class-activator.php
index 476bbd4..61d470e 100755
--- a/includes/class-activator.php
+++ b/includes/class-activator.php
@@ -242,4 +242,29 @@ class PRAutoBlogger_Activator {
 
 		update_option( 'prautoblogger_migrated_run_id_meta_v081', '1' );
 	}
+
+	/**
+	 * v0.9.0 migration: flip legacy default image model to Runware schnell
+	 * and re-derive provider. CEO decision 2026-04-21 — 65× cheaper than
+	 * Gemini Nano Banana. Explicit user selections are preserved.
+	 *
+	 * Side effects: may update `prautoblogger_image_model`,
+	 *               `prautoblogger_image_provider`, and sets the
+	 *               `prautoblogger_migrated_default_image_v090` flag.
+	 */
+	public static function migrate_default_image_v090(): void {
+		if ( get_option( 'prautoblogger_migrated_default_image_v090' ) ) {
+			return;
+		}
+		$curr = (string) get_option( 'prautoblogger_image_model', '' );
+		if ( in_array( $curr, [ '', 'google/gemini-2.5-flash-image' ], true ) ) {
+			update_option( 'prautoblogger_image_model', 'runware:100@1' );
+		}
+		$final = (string) get_option( 'prautoblogger_image_model', 'runware:100@1' );
+		$prov  = PRAutoBlogger_Image_Model_Registry::provider_for( $final );
+		if ( '' !== $prov ) {
+			update_option( 'prautoblogger_image_provider', $prov );
+		}
+		update_option( 'prautoblogger_migrated_default_image_v090', '1' );
+	}
 }
diff --git a/includes/class-prautoblogger.php b/includes/class-prautoblogger.php
index d1e5878..30a2c9a 100644
--- a/includes/class-prautoblogger.php
+++ b/includes/class-prautoblogger.php
@@ -232,9 +232,12 @@ class PRAutoBlogger {
 			update_option( 'prautoblogger_migrated_style_suffix_v4', '1' );
 		}
 
+		// v0.9.0: flip legacy default image model to Runware schnell.
+		PRAutoBlogger_Activator::migrate_default_image_v090();
+
 		// One-time migration: re-wrap existing encrypted values with "enc:" prefix.
 		if ( ! get_option( 'prautoblogger_migrated_enc_prefix' ) ) {
-			$enc_options = [ 'prautoblogger_openrouter_api_key', 'prautoblogger_ga4_credentials_json' ];
+			$enc_options = [ 'prautoblogger_openrouter_api_key', 'prautoblogger_ga4_credentials_json', 'prautoblogger_runware_api_key' ];
 			foreach ( $enc_options as $opt ) {
 				$val = get_option( $opt, '' );
 				if ( '' !== $val && ! PRAutoBlogger_Encryption::is_encrypted( $val ) ) {
diff --git a/includes/core/class-image-pipeline.php b/includes/core/class-image-pipeline.php
index 7910d58..6d303fe 100644
--- a/includes/core/class-image-pipeline.php
+++ b/includes/core/class-image-pipeline.php
@@ -17,22 +17,19 @@ declare(strict_types=1);
 class PRAutoBlogger_Image_Pipeline {
 
 	/**
-	 * Default image dimensions (landscape).
+	 * Default image dimensions (landscape). 1200×632 is the closest
+	 * 8-aligned pair to the standard OG image size (1200×630). Some
+	 * providers require dimensions divisible by 8.
 	 */
-	// Dimensions must be divisible by 8 (required by some providers).
-	// 1200×632 is the closest 8-aligned pair to the standard OG image size (1200×630).
 	private const DEFAULT_WIDTH  = 1200;
 	private const DEFAULT_HEIGHT = 632;
 
 	/** @var PRAutoBlogger_Image_Provider_Interface Image gen provider. */
 	private PRAutoBlogger_Image_Provider_Interface $provider;
-
 	/** @var PRAutoBlogger_Image_Prompt_Builder Builds scene + caption from article data. */
 	private PRAutoBlogger_Image_Prompt_Builder $prompt_builder;
-
 	/** @var PRAutoBlogger_Image_Media_Sideloader Downloads images into WP media library. */
 	private PRAutoBlogger_Image_Media_Sideloader $sideloader;
-
 	/** @var PRAutoBlogger_Cost_Tracker Logs image generation spend. */
 	private PRAutoBlogger_Cost_Tracker $cost_tracker;
 
@@ -41,7 +38,7 @@ class PRAutoBlogger_Image_Pipeline {
 	 *
 	 * When no provider is injected, the constructor reads the
 	 * `prautoblogger_image_provider` setting and instantiates the
-	 * matching concrete class ('openrouter' or 'cloudflare').
+	 * matching concrete class ('runware', 'openrouter', or 'cloudflare').
 	 *
 	 * @param PRAutoBlogger_Image_Provider_Interface|null $provider Optional provider override.
 	 * @param PRAutoBlogger_Cost_Tracker|null             $cost_tracker Optional cost tracker.
@@ -63,6 +60,9 @@ class PRAutoBlogger_Image_Pipeline {
 	 */
 	private static function create_default_provider(): PRAutoBlogger_Image_Provider_Interface {
 		$provider_id = (string) get_option( 'prautoblogger_image_provider', PRAUTOBLOGGER_DEFAULT_IMAGE_PROVIDER );
+		if ( 'runware' === $provider_id ) {
+			return new PRAutoBlogger_Runware_Image_Provider();
+		}
 		if ( 'openrouter' === $provider_id ) {
 			return new PRAutoBlogger_OpenRouter_Image_Provider();
 		}
diff --git a/includes/core/class-image-prompt-builder.php b/includes/core/class-image-prompt-builder.php
index cc2d35a..6ab2389 100644
--- a/includes/core/class-image-prompt-builder.php
+++ b/includes/core/class-image-prompt-builder.php
@@ -31,12 +31,13 @@ You are a comedy writer and single-panel cartoon creator, like Gary Larson (The
 
 Given an article title and summary about peptides, supplements, or biohacking, create a SINGLE-PANEL COMIC concept. Output TWO parts separated by a blank line:
 
-SCENE: One sentence describing the visual gag — a funny, absurd, or ironic situation related to the article's topic. Use anthropomorphized molecules, lab-coat-wearing animals, befuddled scientists, gym bros encountering peptide science, supplement bottles with personality, or everyday situations with a peptide twist. Keep it simple — one clear visual joke, 1-3 characters max.
+SCENE: One sentence describing the visual gag — a funny, absurd, or ironic situation related to the article's topic. Favor CONCRETE, HUMAN-SCALE scenes: people reacting to things, doctors and patients, scientists in a lab, gym bros with peptide vials, partners at a kitchen table, ordinary objects in ordinary rooms. Keep it simple — one clear visual joke, 1-3 characters max.
 
 CAPTION: A short, punchy caption or speech bubble line (under 15 words) that delivers the punchline. The humor should be dry, nerdy, and accessible — the reader should chuckle even if they only half-understand the science.
 
 Rules:
 - The joke MUST relate to the article's actual subject matter, not generic science humor
+- DO NOT personify molecules, peptides, hormones, proteins, or other chemical structures (no "anthropomorphic molecule", no "cartoon hormone"). Image models render anthropomorphized chemistry as incoherent blobs. If the article is about a substance, show a PERSON reacting to or using the substance; if the article is abstract (a mechanism, a process, a concept), fall back on a human observer reacting to its effect.
 - Characters can have simple cartoon faces (round heads, dot eyes, expressive eyebrows)
 - Keep the scene physically simple — few objects, clear staging, easy to read at thumbnail size
 - The caption should work as a standalone joke even without the image
@@ -44,9 +45,9 @@ Rules:
 - Output ONLY the scene and caption. No preamble, no explanation.
 
 Example output format:
-A muscular gym bro stares in confusion at a tiny vial while a peptide molecule with arms and legs flexes next to him, clearly outperforming him.
+A muscular gym bro stares, deflated, at a tiny glass vial in his hand while his friend squats a barbell effortlessly in the background.
 
-"I've been doing this wrong for three years."
+"They told me the peptide did the work, not the squats."
 PROMPT;
 
 	/**
diff --git a/includes/providers/class-runware-image-batch.php b/includes/providers/class-runware-image-batch.php
new file mode 100644
index 0000000..49ba9ef
--- /dev/null
+++ b/includes/providers/class-runware-image-batch.php
@@ -0,0 +1,294 @@
+<?php
+declare(strict_types=1);
+
+// phpcs:disable WordPress.WP.AlternativeFunctions.curl_curl_init
+// phpcs:disable WordPress.WP.AlternativeFunctions.curl_curl_setopt
+// phpcs:disable WordPress.WP.AlternativeFunctions.curl_curl_close
+// phpcs:disable WordPress.WP.AlternativeFunctions.curl_curl_errno
+// phpcs:disable WordPress.WP.AlternativeFunctions.curl_curl_error
+// phpcs:disable WordPress.WP.AlternativeFunctions.curl_curl_getinfo
+// phpcs:disable WordPress.WP.AlternativeFunctions.curl_curl_multi_init
+// phpcs:disable WordPress.WP.AlternativeFunctions.curl_curl_multi_add_handle
+// phpcs:disable WordPress.WP.AlternativeFunctions.curl_curl_multi_exec
+// phpcs:disable WordPress.WP.AlternativeFunctions.curl_curl_multi_select
+// phpcs:disable WordPress.WP.AlternativeFunctions.curl_curl_multi_getcontent
+// phpcs:disable WordPress.WP.AlternativeFunctions.curl_curl_multi_remove_handle
+// phpcs:disable WordPress.WP.AlternativeFunctions.curl_curl_multi_close
+
+/**
+ * Parallel image generation via curl_multi for Runware.
+ *
+ * Fires multiple POST /v1 inference calls concurrently, then fetches
+ * the returned signed image URLs in a second parallel round. Cuts
+ * wall-clock time from N×2s to ~2s regardless of batch size — matches
+ * the Image A/B parallelism pattern already in use for OpenRouter.
+ *
+ * Triggered by: PRAutoBlogger_Runware_Image_Provider::generate_image_batch().
+ * Dependencies: PRAutoBlogger_Runware_Image_Support, PRAutoBlogger_Runware_Image_Pricing,
+ *               PRAutoBlogger_Logger.
+ *
+ * @see class-runware-image-provider.php — Sole caller.
+ * @see class-runware-image-support.php  — Response parsing + image URL fetch.
+ * @see class-open-router-image-batch.php — Sibling pattern for OpenRouter.
+ */
+class PRAutoBlogger_Runware_Image_Batch {
+
+	/** @var PRAutoBlogger_Runware_Image_Pricing */
+	private PRAutoBlogger_Runware_Image_Pricing $pricing;
+
+	/** @var PRAutoBlogger_Runware_Image_Support */
+	private PRAutoBlogger_Runware_Image_Support $support;
+
+	public function __construct(
+		PRAutoBlogger_Runware_Image_Pricing $pricing,
+		PRAutoBlogger_Runware_Image_Support $support
+	) {
+		$this->pricing = $pricing;
+		$this->support = $support;
+	}
+
+	/**
+	 * Execute multiple image generation requests concurrently via curl_multi.
+	 *
+	 * Two parallel rounds: (1) POST /v1 returns signed imageURL per request;
+	 * (2) GET each signed imageURL returns PNG bytes. Each round runs
+	 * concurrently. No retry — single-attempt success rate on schnell >99%.
+	 *
+	 * @param array<string, array{prompt: string, width: int, height: int, options?: array}> $requests Keyed requests.
+	 * @return array<string, array> Image data or `{error}` keyed identically.
+	 */
+	public function execute( array $requests ): array {
+		if ( empty( $requests ) ) {
+			return [];
+		}
+
+		$api_key     = $this->support->get_api_key();
+		$round1      = $this->round_one_inference( $api_key, $requests );
+		$results     = [];
+		$to_download = [];
+
+		foreach ( $round1 as $key => $entry ) {
+			if ( isset( $entry['error'] ) ) {
+				$results[ $key ] = [ 'error' => $entry['error'] ];
+				continue;
+			}
+			$to_download[ $key ] = $entry;
+		}
+
+		if ( empty( $to_download ) ) {
+			return $results;
+		}
+
+		$bytes_map = $this->round_two_download( $to_download );
+		foreach ( $to_download as $key => $entry ) {
+			if ( isset( $bytes_map[ $key ]['error'] ) ) {
+				$results[ $key ] = [ 'error' => $bytes_map[ $key ]['error'] ];
+				continue;
+			}
+			$results[ $key ] = [
+				'bytes'      => $bytes_map[ $key ]['bytes'],
+				'mime_type'  => 'image/png',
+				'width'      => $entry['width'],
+				'height'     => $entry['height'],
+				'model'      => $entry['model'],
+				'seed'       => $entry['seed'],
+				'cost_usd'   => $this->pricing->estimate_cost( $entry['width'], $entry['height'], $entry['model'] ),
+				'latency_ms' => (int) ( ( microtime( true ) - $entry['started_at'] ) * 1000 ),
+			];
+		}
+
+		return $results;
+	}
+
+	/**
+	 * Round 1: fire all inference POSTs in parallel.
+	 *
+	 * @param string $api_key  Plaintext API key.
+	 * @param array  $requests Batch requests.
+	 * @return array<string, array> Map of key => {error} | {image_url, width, height, model, seed, started_at}.
+	 */
+	private function round_one_inference( string $api_key, array $requests ): array {
+		$headers     = [ 'Content-Type: application/json' ];
+		$mh          = curl_multi_init();
+		$handles     = [];
+		$start_times = [];
+
+		foreach ( $requests as $key => $req ) {
+			$model  = $this->pricing->resolve_model( (string) ( $req['options']['model'] ?? '' ) );
+			$snap_w = $this->support->snap_dimension( (int) $req['width'] );
+			$snap_h = $this->support->snap_dimension( (int) $req['height'] );
+			$seed   = $this->support->normalize_seed( isset( $req['options']['seed'] ) ? (int) $req['options']['seed'] : null );
+			$steps  = isset( $req['options']['steps'] ) ? (int) $req['options']['steps'] : $this->pricing->default_steps( $model );
+
+			$ch = curl_init();
+			curl_setopt( $ch, CURLOPT_URL, PRAutoBlogger_Runware_Image_Support::API_URL );
+			curl_setopt( $ch, CURLOPT_POST, true );
+			curl_setopt( $ch, CURLOPT_POSTFIELDS, wp_json_encode(
+				$this->build_payload( $api_key, (string) $req['prompt'], $snap_w, $snap_h, $model, $seed, $steps )
+			) );
+			curl_setopt( $ch, CURLOPT_HTTPHEADER, $headers );
+			curl_setopt( $ch, CURLOPT_RETURNTRANSFER, true );
+			curl_setopt( $ch, CURLOPT_TIMEOUT, PRAUTOBLOGGER_API_TIMEOUT_SECONDS );
+			curl_setopt( $ch, CURLOPT_CONNECTTIMEOUT, 10 );
+
+			curl_multi_add_handle( $mh, $ch );
+			$handles[ $key ]     = [
+				'handle' => $ch,
+				'model'  => $model,
+				'width'  => $snap_w,
+				'height' => $snap_h,
+				'seed'   => $seed,
+			];
+			$start_times[ $key ] = microtime( true );
+		}
+
+		$this->run_multi( $mh );
+
+		$out = [];
+		foreach ( $handles as $key => $entry ) {
+			$out[ $key ] = $this->collect_inference_result( (string) $key, $entry, $start_times[ $key ] );
+			curl_multi_remove_handle( $mh, $entry['handle'] );
+			curl_close( $entry['handle'] );
+		}
+		curl_multi_close( $mh );
+
+		return $out;
+	}
+
+	/**
+	 * Round 2: fetch all signed image URLs in parallel.
+	 *
+	 * @param array<string, array> $inferences Map from round one.
+	 * @return array<string, array{bytes?: string, error?: string}>
+	 */
+	private function round_two_download( array $inferences ): array {
+		$mh      = curl_multi_init();
+		$handles = [];
+
+		foreach ( $inferences as $key => $entry ) {
+			$ch = curl_init();
+			curl_setopt( $ch, CURLOPT_URL, $entry['image_url'] );
+			curl_setopt( $ch, CURLOPT_RETURNTRANSFER, true );
+			curl_setopt( $ch, CURLOPT_TIMEOUT, 30 );
+			curl_setopt( $ch, CURLOPT_CONNECTTIMEOUT, 10 );
+			curl_multi_add_handle( $mh, $ch );
+			$handles[ $key ] = $ch;
+		}
+
+		$this->run_multi( $mh );
+
+		$out = [];
+		foreach ( $handles as $key => $ch ) {
+			$errno = curl_errno( $ch );
+			if ( 0 !== $errno ) {
+				$msg = sprintf( 'Runware image download cURL error %d for "%s": %s', $errno, $key, curl_error( $ch ) );
+				PRAutoBlogger_Logger::instance()->error( $msg, 'runware-image-batch' );
+				$out[ $key ] = [ 'error' => $msg ];
+			} else {
+				$code = (int) curl_getinfo( $ch, CURLINFO_HTTP_CODE );
+				$body = (string) curl_multi_getcontent( $ch );
+				if ( 200 !== $code || '' === $body ) {
+					$msg = sprintf( 'Runware image download HTTP %d for "%s" (%d bytes)', $code, $key, strlen( $body ) );
+					PRAutoBlogger_Logger::instance()->error( $msg, 'runware-image-batch' );
+					$out[ $key ] = [ 'error' => $msg ];
+				} else {
+					$out[ $key ] = [ 'bytes' => $body ];
+				}
+			}
+			curl_multi_remove_handle( $mh, $ch );
+			curl_close( $ch );
+		}
+		curl_multi_close( $mh );
+
+		return $out;
+	}
+
+	/**
+	 * Drive curl_multi_exec to completion.
+	 *
+	 * @param \CurlMultiHandle $mh Multi handle.
+	 */
+	private function run_multi( $mh ): void {
+		$running = 0;
+		do {
+			$status = curl_multi_exec( $mh, $running );
+			if ( $running > 0 ) {
+				curl_multi_select( $mh, 1.0 );
+			}
+		} while ( $running > 0 && CURLM_OK === $status );
+	}
+
+	/**
+	 * Build the auth+inference task-array body for one image request.
+	 *
+	 * @param string $api_key Plaintext API key.
+	 * @param string $prompt  Prompt text.
+	 * @param int    $width   Snapped width.
+	 * @param int    $height  Snapped height.
+	 * @param string $model   Resolved model id.
+	 * @param int    $seed    Positive seed.
+	 * @param int    $steps   Inference steps.
+	 * @return array<int, array<string, mixed>>
+	 */
+	private function build_payload( string $api_key, string $prompt, int $width, int $height, string $model, int $seed, int $steps ): array {
+		return [
+			[ 'taskType' => 'authentication', 'apiKey' => $api_key ],
+			[
+				'taskType'       => 'imageInference',
+				'taskUUID'       => wp_generate_uuid4(),
+				'positivePrompt' => $prompt,
+				'width'          => $width,
+				'height'         => $height,
+				'model'          => $model,
+				'steps'          => $steps,
+				'numberResults'  => 1,
+				'outputFormat'   => 'PNG',
+				'outputType'     => 'URL',
+				'seed'           => $seed,
+			],
+		];
+	}
+
+	/**
+	 * Parse one round-1 handle into either an error or an imageURL entry.
+	 *
+	 * @param string $key   Request key.
+	 * @param array  $entry Handle entry (handle + model + dims + seed).
+	 * @param float  $start Microtime when this handle was queued.
+	 * @return array Either {error} or {image_url, width, height, model, seed, started_at}.
+	 */
+	private function collect_inference_result( string $key, array $entry, float $start ): array {
+		$ch    = $entry['handle'];
+		$errno = curl_errno( $ch );
+		if ( 0 !== $errno ) {
+			$msg = sprintf( 'Runware batch inference cURL error %d for "%s": %s', $errno, $key, curl_error( $ch ) );
+			PRAutoBlogger_Logger::instance()->error( $msg, 'runware-image-batch' );
+			return [ 'error' => $msg ];
+		}
+
+		$http_code = (int) curl_getinfo( $ch, CURLINFO_HTTP_CODE );
+		$raw       = (string) curl_multi_getcontent( $ch );
+		if ( $http_code >= 400 ) {
+			$msg = sprintf( 'Runware batch inference HTTP %d for "%s": %s', $http_code, $key, substr( $raw, 0, 300 ) );
+			PRAutoBlogger_Logger::instance()->error( $msg, 'runware-image-batch' );
+			return [ 'error' => $msg ];
+		}
+
+		try {
+			$image_url = $this->support->extract_image_url( $raw );
+		} catch ( \Throwable $e ) {
+			$msg = sprintf( 'Runware batch inference parse error for "%s": %s', $key, $e->getMessage() );
+			PRAutoBlogger_Logger::instance()->error( $msg, 'runware-image-batch' );
+			return [ 'error' => $msg ];
+		}
+
+		return [
+			'image_url'  => $image_url,
+			'width'      => (int) $entry['width'],
+			'height'     => (int) $entry['height'],
+			'model'      => (string) $entry['model'],
+			'seed'       => (int) $entry['seed'],
+			'started_at' => $start,
+		];
+	}
+}
diff --git a/includes/providers/class-runware-image-pricing.php b/includes/providers/class-runware-image-pricing.php
new file mode 100644
index 0000000..14a0f4e
--- /dev/null
+++ b/includes/providers/class-runware-image-pricing.php
@@ -0,0 +1,118 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * Pricing + model-id resolution helpers for the Runware image provider.
+ *
+ * Each Runware FLUX model has a flat per-image cost sourced from
+ * runware.ai/pricing (April 2026). Unlike OpenRouter models, Runware
+ * prices scale slightly with steps — the quoted rate here assumes the
+ * provider's default step count (4 for schnell, 28 for dev).
+ *
+ * Triggered by: PRAutoBlogger_Runware_Image_Provider, PRAutoBlogger_Runware_Image_Batch.
+ * Dependencies: None — pure calculation + option reads.
+ *
+ * @see class-runware-image-provider.php — Primary caller.
+ * @see class-open-router-image-pricing.php — Sibling pattern for OpenRouter.
+ */
+class PRAutoBlogger_Runware_Image_Pricing {
+
+	/**
+	 * Flat per-image cost (USD) for each supported Runware model, April 2026.
+	 * Update here when Runware reprices or new models launch.
+	 *
+	 * Runware model IDs use `family:variant@version` form. The two FLUX
+	 * variants we support are the CEO-sanctioned defaults.
+	 *
+	 * @var array<string, float>
+	 */
+	private const COST_PER_IMAGE = [
+		// FLUX.1 schnell — 4-step distilled. Our new default (2026-04-21).
+		'runware:100@1' => 0.0006,
+		// FLUX.1 dev — 28-step full model. Higher fidelity, ~30x cost.
+		'runware:101@1' => 0.02,
+	];
+
+	/**
+	 * Default number of inference steps per model. Runware bills per image
+	 * at the model's standard step count; custom step counts may alter price.
+	 *
+	 * @var array<string, int>
+	 */
+	private const DEFAULT_STEPS = [
+		'runware:100@1' => 4,
+		'runware:101@1' => 28,
+	];
+
+	/**
+	 * Resolve the model identifier from a hint, falling back to site option,
+	 * then to the PRAUTOBLOGGER_DEFAULT_IMAGE_MODEL constant.
+	 *
+	 * If the saved/default model is not a Runware id (e.g. still points at
+	 * a Gemini slug), fall back to schnell — the provider was selected
+	 * explicitly, so the user wants a Runware model.
+	 *
+	 * @param string $hint Caller-supplied model identifier (may be empty).
+	 * @return string Runware model id.
+	 */
+	public function resolve_model( string $hint ): string {
+		$candidate = trim( $hint );
+		if ( '' === $candidate ) {
+			$candidate = trim( (string) get_option( 'prautoblogger_image_model', '' ) );
+		}
+		if ( '' === $candidate && defined( 'PRAUTOBLOGGER_DEFAULT_IMAGE_MODEL' ) ) {
+			$candidate = (string) PRAUTOBLOGGER_DEFAULT_IMAGE_MODEL;
+		}
+
+		// If the candidate isn't a known Runware id, fall back to schnell.
+		if ( '' === $candidate || ! isset( self::COST_PER_IMAGE[ $candidate ] ) ) {
+			return 'runware:100@1';
+		}
+
+		return $candidate;
+	}
+
+	/**
+	 * Estimate USD cost for a single image at the given model.
+	 *
+	 * Runware FLUX pricing is flat per image at the model's standard step
+	 * count. Width/height are accepted for interface compatibility but do
+	 * not affect cost for the variants we support.
+	 *
+	 * @param int    $width  Width in pixels (unused for flat pricing).
+	 * @param int    $height Height in pixels (unused for flat pricing).
+	 * @param string $model  Resolved Runware model id.
+	 * @return float USD cost rounded to 6 decimals.
+	 */
+	public function estimate_cost( int $width, int $height, string $model ): float {
+		if ( isset( self::COST_PER_IMAGE[ $model ] ) ) {
+			return round( self::COST_PER_IMAGE[ $model ], 6 );
+		}
+
+		// Unknown model — log it and use a conservative $0.01 estimate.
+		PRAutoBlogger_Logger::instance()->warning(
+			sprintf( 'No Runware pricing data for model "%s". Using $0.01 estimate.', $model ),
+			'runware-image'
+		);
+		return 0.01;
+	}
+
+	/**
+	 * Get the default step count for a Runware model.
+	 *
+	 * @param string $model Resolved Runware model id.
+	 * @return int Default steps.
+	 */
+	public function default_steps( string $model ): int {
+		return self::DEFAULT_STEPS[ $model ] ?? 4;
+	}
+
+	/**
+	 * Get the full model cost table for admin display.
+	 *
+	 * @return array<string, float> Model id => cost per image in USD.
+	 */
+	public static function get_model_costs(): array {
+		return self::COST_PER_IMAGE;
+	}
+}
diff --git a/includes/providers/class-runware-image-provider.php b/includes/providers/class-runware-image-provider.php
new file mode 100644
index 0000000..a43b2c7
--- /dev/null
+++ b/includes/providers/class-runware-image-provider.php
@@ -0,0 +1,294 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * Runware image provider — FLUX.1 schnell / dev via runware.ai.
+ *
+ * Default image backend as of 2026-04-21: schnell (runware:100@1) at
+ * ~$0.0006/image, ~2s latency. 65× cheaper than Gemini Nano Banana with
+ * quality that reads as "stylistic looseness" for our comic aesthetic.
+ *
+ * Triggered by: PRAutoBlogger_Image_Pipeline during content generation.
+ * Dependencies: Runware_Image_Support (key/parsing/backoff),
+ *               Runware_Image_Pricing (model/cost),
+ *               Runware_Image_Batch (parallel curl_multi), Logger.
+ *
+ * @see interface-image-provider.php            — Contract.
+ * @see class-runware-image-batch.php           — Parallel generation via curl_multi.
+ * @see class-runware-image-support.php         — Key, response parsing, retry.
+ * @see class-runware-image-pricing.php         — Model + cost table.
+ * @see class-open-router-image-provider.php    — Sibling pattern for OpenRouter.
+ * @see ARCHITECTURE.md                         — External API Integrations table.
+ */
+class PRAutoBlogger_Runware_Image_Provider implements PRAutoBlogger_Image_Provider_Interface {
+
+	private const PROVIDER_ID      = 'runware';
+	private const MIN_DIMENSION_PX = 64;
+	private const MAX_DIMENSION_PX = 2048;
+
+	/** @var PRAutoBlogger_Runware_Image_Pricing */
+	private PRAutoBlogger_Runware_Image_Pricing $pricing;
+
+	/** @var PRAutoBlogger_Runware_Image_Support */
+	private PRAutoBlogger_Runware_Image_Support $support;
+
+	public function __construct() {
+		$this->pricing = new PRAutoBlogger_Runware_Image_Pricing();
+		$this->support = new PRAutoBlogger_Runware_Image_Support();
+	}
+
+	/**
+	 * {@inheritDoc}
+	 *
+	 * Two-step HTTP flow: POST /v1 returns a signed imageURL, then GET that
+	 * URL for the bytes. Retries 5xx/429 on the POST with exponential
+	 * backoff; 4xx (except 429) fail immediately. The image download GET
+	 * is not retried — signed URLs are short-lived.
+	 */
+	public function generate_image( string $prompt, int $width, int $height, array $options = [] ): array {
+		$this->assert_valid_dimensions( $width, $height );
+		$prompt = trim( $prompt );
+		if ( '' === $prompt ) {
+			throw new \InvalidArgumentException(
+				esc_html__( 'Image prompt cannot be empty.', 'prautoblogger' )
+			);
+		}
+
+		$api_key    = $this->support->get_api_key();
+		$model      = $this->pricing->resolve_model( (string) ( $options['model'] ?? '' ) );
+		$snap_w     = $this->support->snap_dimension( $width );
+		$snap_h     = $this->support->snap_dimension( $height );
+		$seed       = $this->support->normalize_seed( isset( $options['seed'] ) ? (int) $options['seed'] : null );
+		$steps      = isset( $options['steps'] ) ? (int) $options['steps'] : $this->pricing->default_steps( $model );
+		$body       = $this->build_request_body( $api_key, $prompt, $snap_w, $snap_h, $model, $seed, $steps );
+		$headers    = [ 'Content-Type' => 'application/json' ];
+		$started_at = microtime( true );
+		$last_error = '';
+
+		for ( $attempt = 1; $attempt <= PRAUTOBLOGGER_MAX_RETRIES; $attempt++ ) {
+			$response = wp_remote_post( PRAutoBlogger_Runware_Image_Support::API_URL, [
+				'timeout' => PRAUTOBLOGGER_API_TIMEOUT_SECONDS,
+				'headers' => $headers,
+				'body'    => wp_json_encode( $body ),
+			] );
+
+			if ( is_wp_error( $response ) ) {
+				$last_error = $response->get_error_message();
+				$this->support->log_retry( $attempt, 'network', $last_error );
+				$this->support->backoff( $attempt );
+				continue;
+			}
+
+			$status = (int) wp_remote_retrieve_response_code( $response );
+			$raw    = (string) wp_remote_retrieve_body( $response );
+
+			if ( 429 === $status || $status >= 500 ) {
+				$last_error = sprintf( 'HTTP %d: %s', $status, substr( $raw, 0, 300 ) );
+				$this->support->log_retry( $attempt, (string) $status, $last_error );
+				if ( $attempt < PRAUTOBLOGGER_MAX_RETRIES ) {
+					$retry_after = (int) wp_remote_retrieve_header( $response, 'retry-after' );
+					$this->support->backoff( $attempt, $retry_after );
+				}
+				continue;
+			}
+
+			if ( $status >= 400 ) {
+				PRAutoBlogger_Logger::instance()->error(
+					sprintf( 'Runware image gen HTTP %d: %s', $status, substr( $raw, 0, 300 ) ),
+					'runware-image'
+				);
+				throw new \RuntimeException(
+					sprintf(
+						esc_html__( 'Runware image error (HTTP %1$d): %2$s', 'prautoblogger' ),
+						$status,
+						esc_html( substr( $raw, 0, 300 ) )
+					)
+				);
+			}
+
+			$image_url   = $this->support->extract_image_url( $raw );
+			$image_bytes = $this->support->download_image_bytes( $image_url );
+
+			return [
+				'bytes'      => $image_bytes,
+				'mime_type'  => 'image/png',
+				'width'      => $snap_w,
+				'height'     => $snap_h,
+				'model'      => $model,
+				'seed'       => $seed,
+				'cost_usd'   => $this->pricing->estimate_cost( $snap_w, $snap_h, $model ),
+				'latency_ms' => (int) ( ( microtime( true ) - $started_at ) * 1000 ),
+			];
+		}
+
+		throw new \RuntimeException(
+			sprintf(
+				esc_html__( 'Runware image gen failed after %1$d attempts. Last error: %2$s', 'prautoblogger' ),
+				PRAUTOBLOGGER_MAX_RETRIES,
+				esc_html( $last_error )
+			)
+		);
+	}
+
+	/**
+	 * Generate multiple images concurrently via curl_multi.
+	 *
+	 * Delegates to PRAutoBlogger_Runware_Image_Batch, which fires all
+	 * inference POSTs in parallel, then fetches the signed image URLs
+	 * in parallel as well. Wall-clock time ≈ slowest single image.
+	 *
+	 * {@inheritDoc}
+	 */
+	public function generate_image_batch( array $requests ): array {
+		foreach ( $requests as $key => $req ) {
+			$this->assert_valid_dimensions( $req['width'], $req['height'] );
+			if ( '' === trim( $req['prompt'] ) ) {
+				throw new \InvalidArgumentException(
+					sprintf( 'Image prompt for key "%s" cannot be empty.', esc_html( $key ) )
+				);
+			}
+		}
+
+		$batch = new PRAutoBlogger_Runware_Image_Batch( $this->pricing, $this->support );
+
+		PRAutoBlogger_Logger::instance()->info(
+			sprintf( 'Starting parallel Runware image batch (%d images)', count( $requests ) ),
+			'runware-image'
+		);
+
+		return $batch->execute( $requests );
+	}
+
+	/** {@inheritDoc} */
+	public function estimate_cost( int $width, int $height, array $options = [] ): float {
+		$model = $this->pricing->resolve_model( (string) ( $options['model'] ?? '' ) );
+		return $this->pricing->estimate_cost( $width, $height, $model );
+	}
+
+	/** {@inheritDoc} */
+	public function get_provider_name(): string {
+		return self::PROVIDER_ID;
+	}
+
+	/**
+	 * {@inheritDoc}
+	 *
+	 * Runware has no dedicated "validate key" endpoint, so we send a minimal
+	 * authentication task and look for `taskType=authentication` in the
+	 * response data with no accompanying errors.
+	 */
+	public function validate_credentials_detailed(): array {
+		try {
+			$api_key = $this->support->get_api_key();
+		} catch ( \RuntimeException $e ) {
+			return [ 'status' => 'error', 'message' => $e->getMessage() ];
+		}
+
+		$body = [
+			[ 'taskType' => 'authentication', 'apiKey' => $api_key ],
+		];
+
+		$response = wp_remote_post( PRAutoBlogger_Runware_Image_Support::API_URL, [
+			'timeout' => 15,
+			'headers' => [ 'Content-Type' => 'application/json' ],
+			'body'    => wp_json_encode( $body ),
+		] );
+
+		if ( is_wp_error( $response ) ) {
+			return [
+				'status'  => 'error',
+				'message' => __( 'Could not reach Runware API.', 'prautoblogger' ),
+				'debug'   => $response->get_error_message(),
+			];
+		}
+
+		$status = (int) wp_remote_retrieve_response_code( $response );
+		$raw    = (string) wp_remote_retrieve_body( $response );
+
+		if ( 200 !== $status ) {
+			return [
+				'status'  => 'error',
+				'message' => sprintf( __( 'Runware returned HTTP %d.', 'prautoblogger' ), $status ),
+				'debug'   => substr( $raw, 0, 200 ),
+			];
+		}
+
+		$decoded = json_decode( $raw, true );
+		if ( is_array( $decoded ) && isset( $decoded['errors'] ) && ! empty( $decoded['errors'] ) ) {
+			$first = $decoded['errors'][0] ?? [];
+			$msg   = is_array( $first ) ? (string) ( $first['message'] ?? '' ) : (string) $first;
+			return [
+				'status'  => 'error',
+				'message' => __( 'Runware rejected the API key.', 'prautoblogger' ),
+				'debug'   => substr( $msg, 0, 200 ),
+			];
+		}
+
+		return [ 'status' => 'ok', 'message' => __( 'Runware API key valid.', 'prautoblogger' ) ];
+	}
+
+	/**
+	 * Build the JSON task-array body for a single imageInference request.
+	 *
+	 * Runware's single endpoint consumes [auth, inference] in one POST.
+	 *
+	 * @param string $api_key Plaintext API key.
+	 * @param string $prompt  Full prompt text.
+	 * @param int    $width   Snapped width.
+	 * @param int    $height  Snapped height.
+	 * @param string $model   Resolved model id.
+	 * @param int    $seed    Positive seed.
+	 * @param int    $steps   Inference steps.
+	 * @return array<int, array<string, mixed>>
+	 */
+	private function build_request_body(
+		string $api_key,
+		string $prompt,
+		int $width,
+		int $height,
+		string $model,
+		int $seed,
+		int $steps
+	): array {
+		return [
+			[
+				'taskType' => 'authentication',
+				'apiKey'   => $api_key,
+			],
+			[
+				'taskType'       => 'imageInference',
+				'taskUUID'       => wp_generate_uuid4(),
+				'positivePrompt' => $prompt,
+				'width'          => $width,
+				'height'         => $height,
+				'model'          => $model,
+				'steps'          => $steps,
+				'numberResults'  => 1,
+				'outputFormat'   => 'PNG',
+				'outputType'     => 'URL',
+				'seed'           => $seed,
+			],
+		];
+	}
+
+	/**
+	 * Enforce the interface's dimension contract.
+	 *
+	 * @param int $width  Width in pixels.
+	 * @param int $height Height in pixels.
+	 * @throws \InvalidArgumentException If outside [MIN, MAX].
+	 */
+	private function assert_valid_dimensions( int $width, int $height ): void {
+		if (
+			$width < self::MIN_DIMENSION_PX || $width > self::MAX_DIMENSION_PX ||
+			$height < self::MIN_DIMENSION_PX || $height > self::MAX_DIMENSION_PX
+		) {
+			throw new \InvalidArgumentException(
+				sprintf(
+					esc_html__( 'Image dimensions %1$dx%2$d outside supported range (%3$d–%4$d px).', 'prautoblogger' ),
+					$width, $height, self::MIN_DIMENSION_PX, self::MAX_DIMENSION_PX
+				)
+			);
+		}
+	}
+}
diff --git a/includes/providers/class-runware-image-support.php b/includes/providers/class-runware-image-support.php
new file mode 100644
index 0000000..46bd39b
--- /dev/null
+++ b/includes/providers/class-runware-image-support.php
@@ -0,0 +1,219 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * Support helpers for the Runware image provider — API key lookup,
+ * response parsing (URL fetch), retry backoff, and logging.
+ *
+ * Split from the provider to keep both files under the 300-line cap.
+ *
+ * Triggered by: PRAutoBlogger_Runware_Image_Provider, PRAutoBlogger_Runware_Image_Batch.
+ * Dependencies: PRAutoBlogger_Encryption, PRAutoBlogger_Logger.
+ *
+ * @see class-runware-image-provider.php — Primary caller.
+ * @see class-runware-image-batch.php    — Parallel caller.
+ */
+class PRAutoBlogger_Runware_Image_Support {
+
+	/**
+	 * Runware task-based single endpoint. Unlike OpenRouter /chat/completions,
+	 * Runware accepts a JSON array of tasks (auth + inference) at this URL.
+	 */
+	public const API_URL = 'https://api.runware.ai/v1';
+
+	/**
+	 * Get the decrypted Runware API key from settings.
+	 *
+	 * @return string Plaintext key.
+	 * @throws \RuntimeException If key is not configured or decrypt fails.
+	 */
+	public function get_api_key(): string {
+		$stored = (string) get_option( 'prautoblogger_runware_api_key', '' );
+		if ( '' === $stored ) {
+			throw new \RuntimeException(
+				__( 'Runware API key is not configured. Go to PRAutoBlogger → Settings → Images.', 'prautoblogger' )
+			);
+		}
+
+		if ( PRAutoBlogger_Encryption::is_encrypted( $stored ) ) {
+			$decrypted = PRAutoBlogger_Encryption::decrypt( $stored );
+			if ( '' === $decrypted ) {
+				throw new \RuntimeException(
+					__( 'Runware API key could not be decrypted. Re-enter in Settings.', 'prautoblogger' )
+				);
+			}
+			return $decrypted;
+		}
+
+		return $stored;
+	}
+
+	/**
+	 * Extract the image URL from Runware's JSON response body.
+	 *
+	 * The response is `{"data": [{"taskType":"imageInference","imageURL":"..."}]}`.
+	 * We scan `data[]` for the first imageInference entry with a non-empty URL.
+	 *
+	 * @param string $raw Raw JSON response body from POST /v1.
+	 * @return string The imageURL to fetch bytes from.
+	 * @throws \RuntimeException If the response is malformed or contains no image.
+	 */
+	public function extract_image_url( string $raw ): string {
+		$decoded = json_decode( $raw, true );
+		if ( ! is_array( $decoded ) ) {
+			throw new \RuntimeException(
+				esc_html__( 'Runware returned invalid JSON.', 'prautoblogger' )
+			);
+		}
+
+		// Runware wraps errors in an `errors` array.
+		if ( isset( $decoded['errors'] ) && is_array( $decoded['errors'] ) && ! empty( $decoded['errors'] ) ) {
+			$first = $decoded['errors'][0] ?? [];
+			$msg   = is_array( $first )
+				? (string) ( $first['message'] ?? wp_json_encode( $first ) )
+				: (string) $first;
+			throw new \RuntimeException(
+				sprintf(
+					esc_html__( 'Runware upstream error: %s', 'prautoblogger' ),
+					esc_html( substr( $msg, 0, 300 ) )
+				)
+			);
+		}
+
+		$data = $decoded['data'] ?? [];
+		if ( ! is_array( $data ) || empty( $data ) ) {
+			throw new \RuntimeException(
+				esc_html__( 'Runware response contained no data.', 'prautoblogger' )
+			);
+		}
+
+		foreach ( $data as $entry ) {
+			if ( ! is_array( $entry ) ) {
+				continue;
+			}
+			if ( 'imageInference' === ( $entry['taskType'] ?? '' ) ) {
+				$url = (string) ( $entry['imageURL'] ?? '' );
+				if ( '' !== $url ) {
+					return $url;
+				}
+			}
+		}
+
+		throw new \RuntimeException(
+			esc_html__( 'Runware response contained no imageInference imageURL.', 'prautoblogger' )
+		);
+	}
+
+	/**
+	 * Download the image bytes from a signed Runware delivery URL.
+	 *
+	 * Runware returns the image URL separately and bills the inference call;
+	 * downloading is a regular GET against `im.runware.ai`.
+	 *
+	 * @param string $image_url Signed image URL from extract_image_url().
+	 * @return string Raw PNG bytes.
+	 * @throws \RuntimeException On HTTP error or empty body.
+	 */
+	public function download_image_bytes( string $image_url ): string {
+		$response = wp_remote_get( $image_url, [
+			'timeout' => 30,
+		] );
+
+		if ( is_wp_error( $response ) ) {
+			throw new \RuntimeException(
+				sprintf(
+					esc_html__( 'Runware image download failed: %s', 'prautoblogger' ),
+					esc_html( $response->get_error_message() )
+				)
+			);
+		}
+
+		$status = (int) wp_remote_retrieve_response_code( $response );
+		if ( 200 !== $status ) {
+			throw new \RuntimeException(
+				sprintf(
+					esc_html__( 'Runware image download HTTP %d.', 'prautoblogger' ),
+					$status
+				)
+			);
+		}
+
+		$bytes = (string) wp_remote_retrieve_body( $response );
+		if ( '' === $bytes ) {
+			throw new \RuntimeException(
+				esc_html__( 'Runware image download returned empty body.', 'prautoblogger' )
+			);
+		}
+
+		return $bytes;
+	}
+
+	/**
+	 * Snap a target pixel dimension to Runware's FLUX constraints.
+	 *
+	 * FLUX.1 (schnell + dev) requires dimensions divisible by 64, in the
+	 * range [512, 2048]. We round to the nearest multiple of 64 and clamp.
+	 *
+	 * @param int $px Caller-requested pixel dimension.
+	 * @return int Snapped dimension.
+	 */
+	public function snap_dimension( int $px ): int {
+		$snapped = (int) round( $px / 64 ) * 64;
+		if ( $snapped < 512 ) {
+			return 512;
+		}
+		if ( $snapped > 2048 ) {
+			return 2048;
+		}
+		return $snapped;
+	}
+
+	/**
+	 * Normalize a caller seed to Runware's constraint (must be > 0).
+	 *
+	 * @param int|null $seed Caller-supplied seed or null for "random".
+	 * @return int A positive integer seed.
+	 */
+	public function normalize_seed( ?int $seed ): int {
+		if ( null === $seed || $seed < 1 ) {
+			$derived = (int) ( ( microtime( true ) * 1000 ) % 2147483647 );
+			return $derived > 0 ? $derived : 1;
+		}
+		return $seed;
+	}
+
+	/**
+	 * Emit a WARN line for a retryable image-gen failure.
+	 *
+	 * @param int    $attempt 1-based attempt number.
+	 * @param string $class   'network' or HTTP status code string.
+	 * @param string $detail  Short failure detail.
+	 */
+	public function log_retry( int $attempt, string $class, string $detail ): void {
+		PRAutoBlogger_Logger::instance()->warning(
+			sprintf(
+				'Runware image gen %s failure (attempt %d/%d): %s',
+				$class,
+				$attempt,
+				PRAUTOBLOGGER_MAX_RETRIES,
+				$detail
+			),
+			'runware-image'
+		);
+	}
+
+	/**
+	 * Sleep between retries with exponential backoff.
+	 *
+	 * @param int $attempt     1-based attempt that just failed.
+	 * @param int $retry_after Retry-After header value (0 if absent).
+	 */
+	public function backoff( int $attempt, int $retry_after = 0 ): void {
+		$delay = $retry_after > 0
+			? min( $retry_after, 60 )
+			: PRAUTOBLOGGER_RETRY_BASE_DELAY_SECONDS * (int) pow( 2, $attempt - 1 );
+		if ( $delay > 0 ) {
+			sleep( $delay );
+		}
+	}
+}
diff --git a/prautoblogger.php b/prautoblogger.php
index fda4d44..e07fa32 100644
--- a/prautoblogger.php
+++ b/prautoblogger.php
@@ -8,7 +8,7 @@ declare(strict_types=1);
  * Plugin Name:       PRAutoBlogger
  * Plugin URI:        https://peptiderepo.com/prautoblogger
  * Description:       Monitors social media for trending topics, generates SEO-friendly blog posts using AI, and publishes them on a daily schedule with full cost tracking and self-improvement metrics.
- * Version:           0.8.2
+ * Version:           0.9.0
  * Requires at least: 6.0
  * Requires PHP:      7.4
  * Author:            PeptideRepo
@@ -35,7 +35,7 @@ if ( ! defined( 'ABSPATH' ) ) {
 | and limits without magic strings.
 */
 
-define( 'PRAUTOBLOGGER_VERSION', '0.8.2' );
+define( 'PRAUTOBLOGGER_VERSION', '0.9.0' );
 define( 'PRAUTOBLOGGER_DB_VERSION', '1.1.0' );
 define( 'PRAUTOBLOGGER_PLUGIN_FILE', __FILE__ );
 define( 'PRAUTOBLOGGER_PLUGIN_DIR', plugin_dir_path( __FILE__ ) );
@@ -54,11 +54,13 @@ define( 'PRAUTOBLOGGER_DEFAULT_WRITING_MODEL', 'google/gemini-2.5-flash-lite' );
 define( 'PRAUTOBLOGGER_DEFAULT_EDITOR_MODEL', 'google/gemini-2.5-flash-lite' );
 
 // Image generation defaults.
-// Default provider is OpenRouter; Cloudflare is the fallback.
-// Default model is Gemini 2.5 Flash Image ($0.005/image, good for comics).
-// User can override via Settings → Images → Image Model.
-define( 'PRAUTOBLOGGER_DEFAULT_IMAGE_PROVIDER', 'openrouter' );
-define( 'PRAUTOBLOGGER_DEFAULT_IMAGE_MODEL', 'google/gemini-2.5-flash-image' );
+// Default provider is Runware; OpenRouter (Gemini) + Cloudflare remain as alternates.
+// Default model is FLUX.1 schnell via Runware (~$0.0006/image, ~2s). CEO
+// decision 2026-04-21 after comic A/B: schnell's looser fidelity reads as
+// editorial-cartoon style and is 65× cheaper than Nano Banana. Users can
+// override via Settings → Images → Image Model.
+define( 'PRAUTOBLOGGER_DEFAULT_IMAGE_PROVIDER', 'runware' );
+define( 'PRAUTOBLOGGER_DEFAULT_IMAGE_MODEL', 'runware:100@1' );
 
 // Default style suffix appended to every image-gen prompt. Updated
 // 2026-04-18 v4: single-panel newspaper comic style. Caption is now
diff --git a/tests/unit/Providers/RunwareImagePricingTest.php b/tests/unit/Providers/RunwareImagePricingTest.php
new file mode 100644
index 0000000..a1871ee
--- /dev/null
+++ b/tests/unit/Providers/RunwareImagePricingTest.php
@@ -0,0 +1,91 @@
+<?php
+/**
+ * Tests for PRAutoBlogger_Runware_Image_Pricing.
+ *
+ * Validates model resolution fallback logic and per-image cost estimation
+ * for the Runware FLUX models.
+ *
+ * @package PRAutoBlogger\Tests\Providers
+ */
+
+namespace PRAutoBlogger\Tests\Providers;
+
+use PRAutoBlogger\Tests\BaseTestCase;
+use Brain\Monkey\Functions;
+
+class RunwareImagePricingTest extends BaseTestCase {
+
+	protected function setUp(): void {
+		parent::setUp();
+		Functions\when( 'get_option' )->alias( function ( $key, $default = false ) {
+			static $options = [];
+			return $options[ $key ] ?? $default;
+		} );
+	}
+
+	/** Empty hint resolves to the v0.9.0 default (runware schnell). */
+	public function test_resolve_model_empty_hint_uses_schnell_default(): void {
+		$pricing = new \PRAutoBlogger_Runware_Image_Pricing();
+		$model   = $pricing->resolve_model( '' );
+		$this->assertSame( 'runware:100@1', $model );
+	}
+
+	/** Explicit schnell hint resolves to itself. */
+	public function test_resolve_model_schnell_hint(): void {
+		$pricing = new \PRAutoBlogger_Runware_Image_Pricing();
+		$this->assertSame( 'runware:100@1', $pricing->resolve_model( 'runware:100@1' ) );
+	}
+
+	/** Explicit dev hint resolves to itself. */
+	public function test_resolve_model_dev_hint(): void {
+		$pricing = new \PRAutoBlogger_Runware_Image_Pricing();
+		$this->assertSame( 'runware:101@1', $pricing->resolve_model( 'runware:101@1' ) );
+	}
+
+	/**
+	 * A non-Runware hint (e.g. a Gemini slug) falls back to schnell because
+	 * the Runware provider was selected explicitly — the user wants a
+	 * Runware model even if the admin option still holds a foreign slug.
+	 */
+	public function test_resolve_model_unknown_hint_falls_back_to_schnell(): void {
+		$pricing = new \PRAutoBlogger_Runware_Image_Pricing();
+		$this->assertSame( 'runware:100@1', $pricing->resolve_model( 'google/gemini-2.5-flash-image' ) );
+	}
+
+	/** FLUX.1 schnell costs ~$0.0006/image. */
+	public function test_estimate_cost_schnell(): void {
+		$pricing = new \PRAutoBlogger_Runware_Image_Pricing();
+		$cost    = $pricing->estimate_cost( 1216, 640, 'runware:100@1' );
+		$this->assertEqualsWithDelta( 0.0006, $cost, 0.000001 );
+	}
+
+	/** FLUX.1 dev costs ~$0.02/image. */
+	public function test_estimate_cost_dev(): void {
+		$pricing = new \PRAutoBlogger_Runware_Image_Pricing();
+		$cost    = $pricing->estimate_cost( 1216, 640, 'runware:101@1' );
+		$this->assertEqualsWithDelta( 0.02, $cost, 0.000001 );
+	}
+
+	/** Unknown model falls back to conservative $0.01 estimate. */
+	public function test_estimate_cost_unknown_model(): void {
+		$pricing = new \PRAutoBlogger_Runware_Image_Pricing();
+		$cost    = $pricing->estimate_cost( 1216, 640, 'runware:999@1' );
+		$this->assertEqualsWithDelta( 0.01, $cost, 0.000001 );
+	}
+
+	/** Default step count: schnell=4, dev=28. */
+	public function test_default_steps(): void {
+		$pricing = new \PRAutoBlogger_Runware_Image_Pricing();
+		$this->assertSame( 4, $pricing->default_steps( 'runware:100@1' ) );
+		$this->assertSame( 28, $pricing->default_steps( 'runware:101@1' ) );
+		$this->assertSame( 4, $pricing->default_steps( 'runware:999@1' ) );
+	}
+
+	/** get_model_costs returns a non-empty map with Runware models. */
+	public function test_get_model_costs(): void {
+		$costs = \PRAutoBlogger_Runware_Image_Pricing::get_model_costs();
+		$this->assertIsArray( $costs );
+		$this->assertArrayHasKey( 'runware:100@1', $costs );
+		$this->assertArrayHasKey( 'runware:101@1', $costs );
+	}
+}
diff --git a/tests/unit/Providers/RunwareImageProviderTest.php b/tests/unit/Providers/RunwareImageProviderTest.php
new file mode 100644
index 0000000..9788110
--- /dev/null
+++ b/tests/unit/Providers/RunwareImageProviderTest.php
@@ -0,0 +1,247 @@
+<?php
+/**
+ * Tests for PRAutoBlogger_Runware_Image_Provider.
+ *
+ * Validates interface compliance, two-step POST-then-GET flow, retry
+ * behavior on 5xx, immediate-fail on 4xx, and dimension/prompt guards.
+ * All HTTP calls are mocked — no real API traffic.
+ *
+ * @package PRAutoBlogger\Tests\Providers
+ */
+
+namespace PRAutoBlogger\Tests\Providers;
+
+use PRAutoBlogger\Tests\BaseTestCase;
+use Brain\Monkey\Functions;
+
+class RunwareImageProviderTest extends BaseTestCase {
+
+	protected function setUp(): void {
+		parent::setUp();
+
+		Functions\when( 'get_option' )->alias( function ( $key, $default = false ) {
+			static $options = [
+				'prautoblogger_runware_api_key' => 'enc:fake-key',
+				'prautoblogger_image_model'     => 'runware:100@1',
+			];
+			return $options[ $key ] ?? $default;
+		} );
+
+		Functions\when( 'is_wp_error' )->alias( function ( $thing ) {
+			return $thing instanceof \WP_Error;
+		} );
+
+		Functions\when( 'wp_generate_uuid4' )->justReturn( '11111111-2222-3333-4444-555555555555' );
+
+		if ( ! class_exists( 'PRAutoBlogger_Encryption' ) ) {
+			eval( '
+				class PRAutoBlogger_Encryption {
+					public static function is_encrypted( $v ) { return 0 === strpos( $v, "enc:" ); }
+					public static function decrypt( $v ) { return "rw-test-key-123"; }
+					public static function encrypt( $v ) { return "enc:" . $v; }
+				}
+			' );
+		}
+	}
+
+	/** Provider name is 'runware'. */
+	public function test_get_provider_name(): void {
+		$provider = new \PRAutoBlogger_Runware_Image_Provider();
+		$this->assertSame( 'runware', $provider->get_provider_name() );
+	}
+
+	/** estimate_cost returns a positive float for schnell. */
+	public function test_estimate_cost_schnell(): void {
+		$provider = new \PRAutoBlogger_Runware_Image_Provider();
+		$cost     = $provider->estimate_cost( 1216, 640, [ 'model' => 'runware:100@1' ] );
+		$this->assertIsFloat( $cost );
+		$this->assertEqualsWithDelta( 0.0006, $cost, 0.000001 );
+	}
+
+	/** estimate_cost returns higher value for dev. */
+	public function test_estimate_cost_dev_higher_than_schnell(): void {
+		$provider = new \PRAutoBlogger_Runware_Image_Provider();
+		$schnell  = $provider->estimate_cost( 1216, 640, [ 'model' => 'runware:100@1' ] );
+		$dev      = $provider->estimate_cost( 1216, 640, [ 'model' => 'runware:101@1' ] );
+		$this->assertGreaterThan( $schnell, $dev );
+	}
+
+	/** Empty prompt throws InvalidArgumentException. */
+	public function test_generate_image_empty_prompt_throws(): void {
+		$provider = new \PRAutoBlogger_Runware_Image_Provider();
+		$this->expectException( \InvalidArgumentException::class );
+		$provider->generate_image( '', 1200, 640 );
+	}
+
+	/** Whitespace-only prompt throws InvalidArgumentException. */
+	public function test_generate_image_whitespace_prompt_throws(): void {
+		$provider = new \PRAutoBlogger_Runware_Image_Provider();
+		$this->expectException( \InvalidArgumentException::class );
+		$provider->generate_image( "   \t\n  ", 1200, 640 );
+	}
+
+	/** Dimension below minimum throws. */
+	public function test_generate_image_tiny_dimensions_throws(): void {
+		$provider = new \PRAutoBlogger_Runware_Image_Provider();
+		$this->expectException( \InvalidArgumentException::class );
+		$provider->generate_image( 'A test prompt', 10, 10 );
+	}
+
+	/** Dimension above maximum throws. */
+	public function test_generate_image_huge_dimensions_throws(): void {
+		$provider = new \PRAutoBlogger_Runware_Image_Provider();
+		$this->expectException( \InvalidArgumentException::class );
+		$provider->generate_image( 'A test prompt', 5000, 5000 );
+	}
+
+	/** Happy path: POST returns URL, GET returns bytes, result shape correct. */
+	public function test_generate_image_success(): void {
+		$image_url  = 'https://im.runware.ai/image/abc.png';
+		$post_body  = wp_json_encode( [
+			'data' => [
+				[ 'taskType' => 'imageInference', 'imageURL' => $image_url ],
+			],
+		] );
+		$fake_bytes = 'fake-png-bytes';
+
+		Functions\when( 'wp_remote_post' )->justReturn( [
+			'response' => [ 'code' => 200 ],
+			'headers'  => [],
+			'body'     => $post_body,
+		] );
+		Functions\when( 'wp_remote_get' )->justReturn( [
+			'response' => [ 'code' => 200 ],
+			'body'     => $fake_bytes,
+		] );
+		Functions\when( 'wp_remote_retrieve_response_code' )->alias( function ( $r ) {
+			return isset( $r['response']['code'] ) ? (int) $r['response']['code'] : 0;
+		} );
+		Functions\when( 'wp_remote_retrieve_body' )->alias( function ( $r ) {
+			return isset( $r['body'] ) ? (string) $r['body'] : '';
+		} );
+		Functions\when( 'wp_remote_retrieve_header' )->justReturn( '' );
+
+		$provider = new \PRAutoBlogger_Runware_Image_Provider();
+		$result   = $provider->generate_image( 'A gym bro holding a vial', 1200, 632 );
+
+		$this->assertArrayHasKey( 'bytes', $result );
+		$this->assertArrayHasKey( 'mime_type', $result );
+		$this->assertArrayHasKey( 'width', $result );
+		$this->assertArrayHasKey( 'height', $result );
+		$this->assertArrayHasKey( 'model', $result );
+		$this->assertArrayHasKey( 'seed', $result );
+		$this->assertArrayHasKey( 'cost_usd', $result );
+		$this->assertArrayHasKey( 'latency_ms', $result );
+
+		$this->assertSame( $fake_bytes, $result['bytes'] );
+		$this->assertSame( 'image/png', $result['mime_type'] );
+		// Snapped to multiples of 64: 1200 → 1216, 632 → 640.
+		$this->assertSame( 1216, $result['width'] );
+		$this->assertSame( 640, $result['height'] );
+		$this->assertSame( 'runware:100@1', $result['model'] );
+		$this->assertGreaterThan( 0, $result['seed'] );
+	}
+
+	/** 4xx (non-429) fails immediately with RuntimeException. */
+	public function test_generate_image_4xx_throws_immediately(): void {
+		Functions\when( 'wp_remote_post' )->justReturn( [
+			'response' => [ 'code' => 401 ],
+			'headers'  => [],
+			'body'     => '{"errors":[{"message":"invalid key"}]}',
+		] );
+		Functions\when( 'wp_remote_retrieve_response_code' )->justReturn( 401 );
+		Functions\when( 'wp_remote_retrieve_body' )->justReturn( '{"errors":[{"message":"invalid key"}]}' );
+		Functions\when( 'wp_remote_retrieve_header' )->justReturn( '' );
+
+		$provider = new \PRAutoBlogger_Runware_Image_Provider();
+		$this->expectException( \RuntimeException::class );
+		$this->expectExceptionMessage( 'HTTP 401' );
+		$provider->generate_image( 'A test prompt', 1200, 632 );
+	}
+
+	/** 5xx triggers retry loop and eventually throws after PRAUTOBLOGGER_MAX_RETRIES. */
+	public function test_generate_image_5xx_retries_then_throws(): void {
+		$call_count = 0;
+		Functions\when( 'wp_remote_post' )->alias( function () use ( &$call_count ) {
+			$call_count++;
+			return [
+				'response' => [ 'code' => 503 ],
+				'headers'  => [],
+				'body'     => '{"errors":[{"message":"temporarily unavailable"}]}',
+			];
+		} );
+		Functions\when( 'wp_remote_retrieve_response_code' )->justReturn( 503 );
+		Functions\when( 'wp_remote_retrieve_body' )->justReturn( '{"errors":[{"message":"temporarily unavailable"}]}' );
+		Functions\when( 'wp_remote_retrieve_header' )->justReturn( '' );
+
+		$provider = new \PRAutoBlogger_Runware_Image_Provider();
+		try {
+			$provider->generate_image( 'A test prompt', 1200, 632 );
+			$this->fail( 'Expected RuntimeException after max retries' );
+		} catch ( \RuntimeException $e ) {
+			$this->assertSame(
+				PRAUTOBLOGGER_MAX_RETRIES,
+				$call_count,
+				'Provider must attempt exactly PRAUTOBLOGGER_MAX_RETRIES times before giving up.'
+			);
+		}
+	}
+
+	/** errors[] in a 200 body is treated as an upstream error. */
+	public function test_generate_image_errors_in_200_body_throws(): void {
+		$body = wp_json_encode( [
+			'errors' => [ [ 'message' => 'moderation rejected' ] ],
+		] );
+		Functions\when( 'wp_remote_post' )->justReturn( [
+			'response' => [ 'code' => 200 ],
+			'headers'  => [],
+			'body'     => $body,
+		] );
+		Functions\when( 'wp_remote_retrieve_response_code' )->justReturn( 200 );
+		Functions\when( 'wp_remote_retrieve_body' )->justReturn( $body );
+		Functions\when( 'wp_remote_retrieve_header' )->justReturn( '' );
+
+		$provider = new \PRAutoBlogger_Runware_Image_Provider();
+		$this->expectException( \RuntimeException::class );
+		$provider->generate_image( 'A test prompt', 1200, 632 );
+	}
+
+	/** validate_credentials_detailed returns ok for a 200 response with no errors. */
+	public function test_validate_credentials_detailed_ok(): void {
+		Functions\when( 'wp_remote_post' )->justReturn( [
+			'response' => [ 'code' => 200 ],
+			'body'     => '{"data":[{"taskType":"authentication"}]}',
+		] );
+		Functions\when( 'wp_remote_retrieve_response_code' )->justReturn( 200 );
+		Functions\when( 'wp_remote_retrieve_body' )->justReturn( '{"data":[{"taskType":"authentication"}]}' );
+
+		$provider = new \PRAutoBlogger_Runware_Image_Provider();
+		$result   = $provider->validate_credentials_detailed();
+		$this->assertSame( 'ok', $result['status'] );
+	}
+
+	/** validate_credentials_detailed returns error when key missing. */
+	public function test_validate_credentials_detailed_missing_key(): void {
+		Functions\when( 'get_option' )->alias( function ( $key, $default = false ) {
+			return $default;
+		} );
+
+		$provider = new \PRAutoBlogger_Runware_Image_Provider();
+		$result   = $provider->validate_credentials_detailed();
+		$this->assertSame( 'error', $result['status'] );
+	}
+
+	/** validate_credentials_detailed returns error when response contains errors[]. */
+	public function test_validate_credentials_detailed_rejected_key(): void {
+		Functions\when( 'wp_remote_post' )->justReturn( [
+			'response' => [ 'code' => 200 ],
+			'body'     => '{"errors":[{"message":"invalid key"}]}',
+		] );
+		Functions\when( 'wp_remote_retrieve_response_code' )->justReturn( 200 );
+		Functions\when( 'wp_remote_retrieve_body' )->justReturn( '{"errors":[{"message":"invalid key"}]}' );
+
+		$provider = new \PRAutoBlogger_Runware_Image_Provider();
+		$result   = $provider->validate_credentials_detailed();
+		$this->assertSame( 'error', $result['status'] );
+	}
+}
diff --git a/tests/unit/Providers/RunwareImageSupportTest.php b/tests/unit/Providers/RunwareImageSupportTest.php
new file mode 100644
index 0000000..aab8b8a
--- /dev/null
+++ b/tests/unit/Providers/RunwareImageSupportTest.php
@@ -0,0 +1,184 @@
+<?php
+/**
+ * Tests for PRAutoBlogger_Runware_Image_Support.
+ *
+ * Covers response parsing (URL extraction), dimension snapping to FLUX
+ * constraints, seed normalization, and API-key lookup.
+ *
+ * @package PRAutoBlogger\Tests\Providers
+ */
+
+namespace PRAutoBlogger\Tests\Providers;
+
+use PRAutoBlogger\Tests\BaseTestCase;
+use Brain\Monkey\Functions;
+
+class RunwareImageSupportTest extends BaseTestCase {
+
+	protected function setUp(): void {
+		parent::setUp();
+
+		Functions\when( 'esc_html' )->returnArg();
+		Functions\when( 'esc_html__' )->returnArg();
+		Functions\when( '__' )->returnArg();
+
+		if ( ! class_exists( 'PRAutoBlogger_Encryption' ) ) {
+			eval( '
+				class PRAutoBlogger_Encryption {
+					public static function is_encrypted( $v ) { return 0 === strpos( $v, "enc:" ); }
+					public static function decrypt( $v ) { return "rw-test-key-123"; }
+					public static function encrypt( $v ) { return "enc:" . $v; }
+				}
+			' );
+		}
+	}
+
+	/** A well-formed imageInference entry returns its imageURL. */
+	public function test_extract_image_url_valid_response(): void {
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$raw     = wp_json_encode( [
+			'data' => [
+				[
+					'taskType' => 'imageInference',
+					'imageURL' => 'https://im.runware.ai/image/abc123.png',
+				],
+			],
+		] );
+		$this->assertSame(
+			'https://im.runware.ai/image/abc123.png',
+			$support->extract_image_url( $raw )
+		);
+	}
+
+	/** An errors[] array in the response causes a RuntimeException. */
+	public function test_extract_image_url_error_response_throws(): void {
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$raw     = wp_json_encode( [
+			'errors' => [
+				[ 'message' => 'invalid api key' ],
+			],
+		] );
+		$this->expectException( \RuntimeException::class );
+		$this->expectExceptionMessage( 'invalid api key' );
+		$support->extract_image_url( $raw );
+	}
+
+	/** Malformed JSON throws RuntimeException. */
+	public function test_extract_image_url_invalid_json_throws(): void {
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$this->expectException( \RuntimeException::class );
+		$support->extract_image_url( 'not json at all' );
+	}
+
+	/** Data array present but no imageInference entry throws. */
+	public function test_extract_image_url_no_inference_entry_throws(): void {
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$raw     = wp_json_encode( [
+			'data' => [
+				[ 'taskType' => 'authentication' ],
+			],
+		] );
+		$this->expectException( \RuntimeException::class );
+		$support->extract_image_url( $raw );
+	}
+
+	/** imageInference present but empty imageURL throws. */
+	public function test_extract_image_url_empty_url_throws(): void {
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$raw     = wp_json_encode( [
+			'data' => [
+				[ 'taskType' => 'imageInference', 'imageURL' => '' ],
+			],
+		] );
+		$this->expectException( \RuntimeException::class );
+		$support->extract_image_url( $raw );
+	}
+
+	/** snap_dimension rounds to nearest multiple of 64. */
+	public function test_snap_dimension_rounds_to_64(): void {
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$this->assertSame( 1216, $support->snap_dimension( 1200 ) );
+		$this->assertSame( 640, $support->snap_dimension( 632 ) );
+		$this->assertSame( 1024, $support->snap_dimension( 1024 ) );
+		$this->assertSame( 1024, $support->snap_dimension( 1050 ) );
+	}
+
+	/** snap_dimension clamps to minimum 512. */
+	public function test_snap_dimension_clamps_min(): void {
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$this->assertSame( 512, $support->snap_dimension( 64 ) );
+		$this->assertSame( 512, $support->snap_dimension( 200 ) );
+	}
+
+	/** snap_dimension clamps to maximum 2048. */
+	public function test_snap_dimension_clamps_max(): void {
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$this->assertSame( 2048, $support->snap_dimension( 4096 ) );
+		$this->assertSame( 2048, $support->snap_dimension( 2500 ) );
+	}
+
+	/** A valid positive seed passes through unchanged. */
+	public function test_normalize_seed_positive_passthrough(): void {
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$this->assertSame( 42, $support->normalize_seed( 42 ) );
+		$this->assertSame( 1234567, $support->normalize_seed( 1234567 ) );
+	}
+
+	/** Null seed derives a positive integer. */
+	public function test_normalize_seed_null_derives_positive(): void {
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$seed    = $support->normalize_seed( null );
+		$this->assertGreaterThan( 0, $seed );
+	}
+
+	/** Zero seed is replaced with a derived positive integer. */
+	public function test_normalize_seed_zero_replaced(): void {
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$seed    = $support->normalize_seed( 0 );
+		$this->assertGreaterThan( 0, $seed );
+	}
+
+	/** Negative seed is replaced with a derived positive integer. */
+	public function test_normalize_seed_negative_replaced(): void {
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$seed    = $support->normalize_seed( -5 );
+		$this->assertGreaterThan( 0, $seed );
+	}
+
+	/** Missing API key option throws RuntimeException. */
+	public function test_get_api_key_missing_throws(): void {
+		Functions\when( 'get_option' )->alias( function ( $key, $default = false ) {
+			return $default;
+		} );
+
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$this->expectException( \RuntimeException::class );
+		$support->get_api_key();
+	}
+
+	/** Encrypted key is decrypted on read. */
+	public function test_get_api_key_decrypts_encrypted(): void {
+		Functions\when( 'get_option' )->alias( function ( $key, $default = false ) {
+			if ( 'prautoblogger_runware_api_key' === $key ) {
+				return 'enc:stored-ciphertext';
+			}
+			return $default;
+		} );
+
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$this->assertSame( 'rw-test-key-123', $support->get_api_key() );
+	}
+
+	/** A plaintext key (pre-migration) passes through unchanged. */
+	public function test_get_api_key_plaintext_passthrough(): void {
+		Functions\when( 'get_option' )->alias( function ( $key, $default = false ) {
+			if ( 'prautoblogger_runware_api_key' === $key ) {
+				return 'rw-plain-key';
+			}
+			return $default;
+		} );
+
+		$support = new \PRAutoBlogger_Runware_Image_Support();
+		$this->assertSame( 'rw-plain-key', $support->get_api_key() );
+	}
+}
diff --git a/tests/unit/Services/ImageModelRegistryTest.php b/tests/unit/Services/ImageModelRegistryTest.php
index f6235c1..b35ccce 100644
--- a/tests/unit/Services/ImageModelRegistryTest.php
+++ b/tests/unit/Services/ImageModelRegistryTest.php
@@ -18,7 +18,7 @@ class ImageModelRegistryTest extends BaseTestCase {
 
 	/**
 	 * Every entry returned by get_models() must carry a non-empty id and
-	 * a provider of 'openrouter' or 'cloudflare'. If this breaks, the
+	 * a provider of 'runware', 'openrouter', or 'cloudflare'. If this breaks, the
 	 * admin save flow will silently drop the provider derivation.
 	 */
 	public function test_every_registry_entry_has_id_and_known_provider(): void {
@@ -31,7 +31,7 @@ class ImageModelRegistryTest extends BaseTestCase {
 			$this->assertArrayHasKey( 'provider', $model );
 			$this->assertContains(
 				$model['provider'],
-				[ 'openrouter', 'cloudflare' ],
+				[ 'runware', 'openrouter', 'cloudflare' ],
 				sprintf( 'Unexpected provider %s for model %s', (string) $model['provider'], (string) $model['id'] )
 			);
 		}
@@ -52,6 +52,22 @@ class ImageModelRegistryTest extends BaseTestCase {
 		);
 	}
 
+	/**
+	 * Runware model ids (added v0.9.0) resolve to the 'runware' provider.
+	 * This test pins the v0.9.0 default flip so a registry regression
+	 * that loses the Runware entries fails CI loudly.
+	 */
+	public function test_provider_for_runware_models(): void {
+		$this->assertSame(
+			'runware',
+			\PRAutoBlogger_Image_Model_Registry::provider_for( 'runware:100@1' )
+		);
+		$this->assertSame(
+			'runware',
+			\PRAutoBlogger_Image_Model_Registry::provider_for( 'runware:101@1' )
+		);
+	}
+
 	/**
 	 * Unknown model ids return an empty string so callers can distinguish
 	 * "not in registry" from a valid provider and show a settings error.