diff --git a/app/Exceptions/Social/BlueskyPublishException.php b/app/Exceptions/Social/BlueskyPublishException.php
new file mode 100644
index 00000000..b6fc6b1a
--- /dev/null
+++ b/app/Exceptions/Social/BlueskyPublishException.php
@@ -0,0 +1,77 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Exceptions\Social;
+
+use App\Exceptions\TokenExpiredException;
+use Illuminate\Http\Client\Response;
+
+class BlueskyPublishException extends SocialPublishException
+{
+    public static function fromApiResponse(mixed $response): static
+    {
+        /** @var Response $response */
+        $status = $response->status();
+        $body = $response->json();
+        $rawResponse = $response->body();
+
+        $error = data_get($body, 'error', '');
+        $errorMessage = data_get($body, 'message', 'An unknown Bluesky error occurred.');
+
+        if (in_array($error, ['ExpiredToken', 'InvalidToken'], true)) {
+            throw new TokenExpiredException(
+                message: $errorMessage,
+                platformErrorCode: $error,
+            );
+        }
+
+        if (str_contains($rawResponse, 'BlobTooLarge') || $status === 413) {
+            return new static(
+                userMessage: "Image exceeds Bluesky's 1MB limit.",
+                category: ErrorCategory::MediaFormat,
+                platformErrorCode: $error ?: null,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        if ($error === 'InvalidRequest') {
+            return new static(
+                userMessage: 'Invalid post data.',
+                category: ErrorCategory::ContentPolicy,
+                platformErrorCode: $error,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        if ($status === 429) {
+            return new static(
+                userMessage: 'Rate limit exceeded. Please try again later.',
+                category: ErrorCategory::RateLimit,
+                platformErrorCode: $error ?: null,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        if ($status >= 500) {
+            return new static(
+                userMessage: 'Bluesky server error. Please try again.',
+                category: ErrorCategory::ServerError,
+                platformErrorCode: $error ?: null,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        return new static(
+            userMessage: $errorMessage,
+            category: ErrorCategory::Unknown,
+            platformErrorCode: $error ?: null,
+            rawResponse: $rawResponse,
+        );
+    }
+
+    public function platform(): string
+    {
+        return 'bluesky';
+    }
+}
diff --git a/app/Exceptions/Social/MastodonPublishException.php b/app/Exceptions/Social/MastodonPublishException.php
new file mode 100644
index 00000000..782f8ab4
--- /dev/null
+++ b/app/Exceptions/Social/MastodonPublishException.php
@@ -0,0 +1,94 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Exceptions\Social;
+
+use App\Exceptions\TokenExpiredException;
+use Illuminate\Http\Client\Response;
+
+class MastodonPublishException extends SocialPublishException
+{
+    public static function fromApiResponse(mixed $response): static
+    {
+        /** @var Response $response */
+        $status = $response->status();
+        $body = $response->json();
+        $rawResponse = $response->body();
+
+        $errorMessage = data_get($body, 'error', 'An unknown Mastodon error occurred.');
+
+        if ($status === 401) {
+            throw new TokenExpiredException(
+                message: $errorMessage,
+                platformErrorCode: (string) $status,
+            );
+        }
+
+        if ($status === 403) {
+            return new static(
+                userMessage: 'This action is not allowed.',
+                category: ErrorCategory::Permission,
+                platformErrorCode: (string) $status,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        if ($status === 422 && str_contains(strtolower($rawResponse), "text can't be blank")) {
+            return new static(
+                userMessage: 'Post text is required when no media is attached.',
+                category: ErrorCategory::ContentPolicy,
+                platformErrorCode: (string) $status,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        if ($status === 422) {
+            return new static(
+                userMessage: 'Media validation failed.',
+                category: ErrorCategory::MediaFormat,
+                platformErrorCode: (string) $status,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        if ($status === 413) {
+            return new static(
+                userMessage: 'File is too large for this Mastodon instance.',
+                category: ErrorCategory::MediaFormat,
+                platformErrorCode: (string) $status,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        if ($status === 429) {
+            return new static(
+                userMessage: 'Rate limit exceeded. Please try again later.',
+                category: ErrorCategory::RateLimit,
+                platformErrorCode: (string) $status,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        if ($status === 503) {
+            return new static(
+                userMessage: 'Mastodon server error. Please try again.',
+                category: ErrorCategory::ServerError,
+                platformErrorCode: (string) $status,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        return new static(
+            userMessage: $errorMessage,
+            category: ErrorCategory::Unknown,
+            platformErrorCode: (string) $status,
+            rawResponse: $rawResponse,
+        );
+    }
+
+    public function platform(): string
+    {
+        return 'mastodon';
+    }
+}
diff --git a/app/Exceptions/Social/PinterestPublishException.php b/app/Exceptions/Social/PinterestPublishException.php
new file mode 100644
index 00000000..58ad92c2
--- /dev/null
+++ b/app/Exceptions/Social/PinterestPublishException.php
@@ -0,0 +1,93 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Exceptions\Social;
+
+use App\Exceptions\TokenExpiredException;
+use Illuminate\Http\Client\Response;
+
+class PinterestPublishException extends SocialPublishException
+{
+    public static function fromApiResponse(mixed $response): static
+    {
+        /** @var Response $response */
+        $status = $response->status();
+        $body = $response->json();
+        $rawResponse = $response->body();
+
+        if ($status === 401) {
+            throw new TokenExpiredException(
+                message: data_get($body, 'message', 'Access token has expired or been revoked'),
+                platformErrorCode: (string) $status,
+            );
+        }
+
+        if ($status === 403) {
+            return new static(
+                userMessage: 'Not authorized to create pins on this board.',
+                category: ErrorCategory::Permission,
+                platformErrorCode: (string) $status,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        if ($status === 429) {
+            return new static(
+                userMessage: 'Rate limit exceeded. Please try again later.',
+                category: ErrorCategory::RateLimit,
+                platformErrorCode: (string) $status,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        if ($status === 400 && str_contains(strtolower($rawResponse), 'board')) {
+            return new static(
+                userMessage: 'Invalid board. Please select a valid board.',
+                category: ErrorCategory::ContentPolicy,
+                platformErrorCode: (string) $status,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        if ($status >= 500) {
+            return new static(
+                userMessage: 'Pinterest server error. Please try again.',
+                category: ErrorCategory::ServerError,
+                platformErrorCode: (string) $status,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        return new static(
+            userMessage: $rawResponse,
+            category: ErrorCategory::Unknown,
+            platformErrorCode: (string) $status,
+            rawResponse: $rawResponse,
+        );
+    }
+
+    public static function fromProcessingStatus(string $status, ?string $rawResponse = null): static
+    {
+        if ($status === 'failed') {
+            return new static(
+                userMessage: 'Media processing failed. Please try a different file.',
+                category: ErrorCategory::MediaFormat,
+                platformErrorCode: null,
+                rawResponse: $rawResponse,
+            );
+        }
+
+        return new static(
+            userMessage: $rawResponse ?? 'An unknown Pinterest error occurred.',
+            category: ErrorCategory::Unknown,
+            platformErrorCode: null,
+            rawResponse: $rawResponse,
+        );
+    }
+
+    public function platform(): string
+    {
+        return 'pinterest';
+    }
+}
diff --git a/tests/Unit/Exceptions/Social/BlueskyPublishExceptionTest.php b/tests/Unit/Exceptions/Social/BlueskyPublishExceptionTest.php
new file mode 100644
index 00000000..3aa52c9a
--- /dev/null
+++ b/tests/Unit/Exceptions/Social/BlueskyPublishExceptionTest.php
@@ -0,0 +1,81 @@
+<?php
+
+declare(strict_types=1);
+
+use App\Exceptions\Social\BlueskyPublishException;
+use App\Exceptions\Social\ErrorCategory;
+use App\Exceptions\TokenExpiredException;
+use Illuminate\Support\Facades\Http;
+
+test('ExpiredToken error throws TokenExpiredException', function () {
+    $response = Http::response(['error' => 'ExpiredToken', 'message' => 'Token has expired.'], 401);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://bsky.social/xrpc/test');
+
+    BlueskyPublishException::fromApiResponse($fakeResponse);
+})->throws(TokenExpiredException::class);
+
+test('InvalidToken error throws TokenExpiredException', function () {
+    $response = Http::response(['error' => 'InvalidToken', 'message' => 'Token is invalid.'], 401);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://bsky.social/xrpc/test');
+
+    BlueskyPublishException::fromApiResponse($fakeResponse);
+})->throws(TokenExpiredException::class);
+
+test('BlobTooLarge in body maps to MediaFormat category', function () {
+    $response = Http::response(['error' => 'BlobTooLarge', 'message' => 'Blob too large.'], 400);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://bsky.social/xrpc/test');
+
+    $exception = BlueskyPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::MediaFormat)
+        ->and($exception->userMessage)->toBe("Image exceeds Bluesky's 1MB limit.");
+});
+
+test('HTTP 429 maps to RateLimit category', function () {
+    $response = Http::response(['error' => 'RateLimitExceeded', 'message' => 'Too many requests.'], 429);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://bsky.social/xrpc/test');
+
+    $exception = BlueskyPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::RateLimit)
+        ->and($exception->userMessage)->toBe('Rate limit exceeded. Please try again later.');
+});
+
+test('unknown error maps to Unknown category with error message', function () {
+    $response = Http::response(['error' => 'SomeUnknownError', 'message' => 'Something went wrong.'], 400);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://bsky.social/xrpc/test');
+
+    $exception = BlueskyPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::Unknown)
+        ->and($exception->userMessage)->toBe('Something went wrong.');
+});
+
+test('InvalidRequest error maps to ContentPolicy category', function () {
+    $response = Http::response(['error' => 'InvalidRequest', 'message' => 'Post data is invalid.'], 400);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://bsky.social/xrpc/test');
+
+    $exception = BlueskyPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::ContentPolicy)
+        ->and($exception->userMessage)->toBe('Invalid post data.');
+});
+
+test('HTTP 500 maps to ServerError category', function () {
+    $response = Http::response(['error' => 'InternalServerError', 'message' => 'Server error.'], 500);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://bsky.social/xrpc/test');
+
+    $exception = BlueskyPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::ServerError)
+        ->and($exception->userMessage)->toBe('Bluesky server error. Please try again.');
+});
+
+test('platform returns bluesky', function () {
+    $response = Http::response(['error' => 'SomeError', 'message' => 'Error.'], 400);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://bsky.social/xrpc/test');
+
+    $exception = BlueskyPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->platform())->toBe('bluesky');
+});
diff --git a/tests/Unit/Exceptions/Social/MastodonPublishExceptionTest.php b/tests/Unit/Exceptions/Social/MastodonPublishExceptionTest.php
new file mode 100644
index 00000000..882932e8
--- /dev/null
+++ b/tests/Unit/Exceptions/Social/MastodonPublishExceptionTest.php
@@ -0,0 +1,84 @@
+<?php
+
+declare(strict_types=1);
+
+use App\Exceptions\Social\ErrorCategory;
+use App\Exceptions\Social\MastodonPublishException;
+use App\Exceptions\TokenExpiredException;
+use Illuminate\Support\Facades\Http;
+
+test('HTTP 401 throws TokenExpiredException', function () {
+    $response = Http::response(['error' => 'The access token is invalid'], 401);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://mastodon.social/api/v1/statuses');
+
+    MastodonPublishException::fromApiResponse($fakeResponse);
+})->throws(TokenExpiredException::class);
+
+test('HTTP 403 maps to Permission category', function () {
+    $response = Http::response(['error' => 'This action is not allowed'], 403);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://mastodon.social/api/v1/statuses');
+
+    $exception = MastodonPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::Permission)
+        ->and($exception->userMessage)->toBe('This action is not allowed.');
+});
+
+test('HTTP 422 with text can\'t be blank maps to ContentPolicy category', function () {
+    $response = Http::response(['error' => "text can't be blank"], 422);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://mastodon.social/api/v1/statuses');
+
+    $exception = MastodonPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::ContentPolicy)
+        ->and($exception->userMessage)->toBe('Post text is required when no media is attached.');
+});
+
+test('HTTP 413 maps to MediaFormat category', function () {
+    $response = Http::response(['error' => 'File too large'], 413);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://mastodon.social/api/v1/statuses');
+
+    $exception = MastodonPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::MediaFormat)
+        ->and($exception->userMessage)->toBe('File is too large for this Mastodon instance.');
+});
+
+test('HTTP 429 maps to RateLimit category', function () {
+    $response = Http::response(['error' => 'Too many requests'], 429);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://mastodon.social/api/v1/statuses');
+
+    $exception = MastodonPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::RateLimit)
+        ->and($exception->userMessage)->toBe('Rate limit exceeded. Please try again later.');
+});
+
+test('HTTP 422 without text blank maps to MediaFormat category', function () {
+    $response = Http::response(['error' => 'Validation failed'], 422);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://mastodon.social/api/v1/statuses');
+
+    $exception = MastodonPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::MediaFormat)
+        ->and($exception->userMessage)->toBe('Media validation failed.');
+});
+
+test('unknown status maps to Unknown category with error message', function () {
+    $response = Http::response(['error' => 'Something went wrong'], 400);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://mastodon.social/api/v1/statuses');
+
+    $exception = MastodonPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::Unknown)
+        ->and($exception->userMessage)->toBe('Something went wrong');
+});
+
+test('platform returns mastodon', function () {
+    $response = Http::response(['error' => 'Some error'], 400);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://mastodon.social/api/v1/statuses');
+
+    $exception = MastodonPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->platform())->toBe('mastodon');
+});
diff --git a/tests/Unit/Exceptions/Social/PinterestPublishExceptionTest.php b/tests/Unit/Exceptions/Social/PinterestPublishExceptionTest.php
new file mode 100644
index 00000000..cbfc348c
--- /dev/null
+++ b/tests/Unit/Exceptions/Social/PinterestPublishExceptionTest.php
@@ -0,0 +1,74 @@
+<?php
+
+declare(strict_types=1);
+
+use App\Exceptions\Social\ErrorCategory;
+use App\Exceptions\Social\PinterestPublishException;
+use App\Exceptions\TokenExpiredException;
+use Illuminate\Support\Facades\Http;
+
+test('HTTP 401 throws TokenExpiredException', function () {
+    $response = Http::response(['message' => 'Access token expired.'], 401);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://api.pinterest.com/test');
+
+    PinterestPublishException::fromApiResponse($fakeResponse);
+})->throws(TokenExpiredException::class);
+
+test('HTTP 429 maps to RateLimit category', function () {
+    $response = Http::response(['message' => 'Too many requests.'], 429);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://api.pinterest.com/test');
+
+    $exception = PinterestPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::RateLimit)
+        ->and($exception->userMessage)->toBe('Rate limit exceeded. Please try again later.');
+});
+
+test('HTTP 403 maps to Permission category', function () {
+    $response = Http::response(['message' => 'Forbidden.'], 403);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://api.pinterest.com/test');
+
+    $exception = PinterestPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::Permission)
+        ->and($exception->userMessage)->toBe('Not authorized to create pins on this board.');
+});
+
+test('HTTP 400 with board in body maps to ContentPolicy category', function () {
+    $response = Http::response(['message' => 'Invalid board_id provided.'], 400);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://api.pinterest.com/test');
+
+    $exception = PinterestPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::ContentPolicy)
+        ->and($exception->userMessage)->toBe('Invalid board. Please select a valid board.');
+});
+
+test('processing status failed maps to MediaFormat category', function () {
+    $exception = PinterestPublishException::fromProcessingStatus('failed');
+
+    expect($exception->category)->toBe(ErrorCategory::MediaFormat)
+        ->and($exception->userMessage)->toBe('Media processing failed. Please try a different file.');
+});
+
+test('processing status unknown maps to Unknown category', function () {
+    $exception = PinterestPublishException::fromProcessingStatus('pending', 'raw response');
+
+    expect($exception->category)->toBe(ErrorCategory::Unknown);
+});
+
+test('HTTP 500 maps to ServerError category', function () {
+    $response = Http::response(['message' => 'Internal server error.'], 500);
+    $fakeResponse = Http::fake(['*' => $response])->post('https://api.pinterest.com/test');
+
+    $exception = PinterestPublishException::fromApiResponse($fakeResponse);
+
+    expect($exception->category)->toBe(ErrorCategory::ServerError)
+        ->and($exception->userMessage)->toBe('Pinterest server error. Please try again.');
+});
+
+test('platform returns pinterest', function () {
+    $exception = PinterestPublishException::fromProcessingStatus('unknown');
+
+    expect($exception->platform())->toBe('pinterest');
+});