diff --git a/AI_API.md b/AI_API.md
index d5e9295..7458b16 100644
--- a/AI_API.md
+++ b/AI_API.md
@@ -82,12 +82,21 @@ Response shape:
     "cms_type": "wordpress",
     "wp_username": "admin",
     "wp_app_password": "abcd 1234 efgh 5678",
+    "api_instructions": null,
     "created_at": "2026-07-19T12:00:00.000000Z",
     "updated_at": "2026-07-19T12:00:00.000000Z"
   }
 }
 ```
 
+`api_instructions` is a free-text field (nullable) for `cms_type=custom`/`other`
+sites — there's no built-in publisher for these yet, so this is where the
+user documents how to actually post there: auth method, endpoints, payload
+shape, whatever's needed. **Read it before improvising** when you're about
+to publish to a site with no wired-in publisher (see "Any other
+network/CMS" below) — it's the site owner telling you directly how their
+API works, rather than you having to guess or ask.
+
 `cms_type` is one of `wordpress`, `custom`, `other`. `wp_username`/
 `wp_app_password` are only meaningful (non-null) when `cms_type` is
 `wordpress` — they're a WordPress **Application Password** pair (see
@@ -269,11 +278,12 @@ integration yet)
 
 There is no built-in publishing path. Do it however is appropriate for
 that platform (its own API, its own automation), using the credentials
-from `GET /api/sites` / `GET /api/accounts`, then report back via
-`PATCH /api/posts/{id}` exactly as described above. This is the general
-fallback contract: **whatever publishes a post, always ends with either
-the `posts:publish` command's automatic bookkeeping, or a manual `PATCH`
-setting `status` and, if applicable, `published_url`.**
+from `GET /api/sites` / `GET /api/accounts` — check the site's
+`api_instructions` first, that's exactly what it's there for — then report
+back via `PATCH /api/posts/{id}` exactly as described above. This is the
+general fallback contract: **whatever publishes a post, always ends with
+either the `posts:publish` command's automatic bookkeeping, or a manual
+`PATCH` setting `status` and, if applicable, `published_url`.**
 
 ## Quick reference
 
diff --git a/app/Http/Resources/SiteResource.php b/app/Http/Resources/SiteResource.php
index 049823e..cce5877 100644
--- a/app/Http/Resources/SiteResource.php
+++ b/app/Http/Resources/SiteResource.php
@@ -17,6 +17,7 @@ class SiteResource extends JsonResource
             'cms_type' => $this->cms_type,
             'wp_username' => $this->wp_username,
             'wp_app_password' => $this->wp_app_password,
+            'api_instructions' => $this->api_instructions,
             'created_at' => $this->created_at,
             'updated_at' => $this->updated_at,
         ];
diff --git a/app/Livewire/Sites/Index.php b/app/Livewire/Sites/Index.php
index b29b8e8..80dcaf5 100644
--- a/app/Livewire/Sites/Index.php
+++ b/app/Livewire/Sites/Index.php
@@ -27,6 +27,8 @@ class Index extends Component
 
     public string $wpAppPassword = '';
 
+    public ?string $apiInstructions = null;
+
     public function render()
     {
         return view('livewire.sites.index', [
@@ -51,6 +53,7 @@ class Index extends Component
         $this->cmsType = $site->cms_type;
         $this->wpUsername = $site->wp_username ?? '';
         $this->wpAppPassword = $site->wp_app_password ?? '';
+        $this->apiInstructions = $site->api_instructions;
         $this->showForm = true;
     }
 
@@ -63,6 +66,7 @@ class Index extends Component
             'cmsType' => ['required', 'string', 'in:' . implode(',', Site::CMS_TYPES)],
             'wpUsername' => ['required_if:cmsType,wordpress', 'nullable', 'string', 'max:255'],
             'wpAppPassword' => ['required_if:cmsType,wordpress', 'nullable', 'string', 'max:255'],
+            'apiInstructions' => ['nullable', 'string'],
         ]);
 
         Site::updateOrCreate(['id' => $this->editingId], [
@@ -72,6 +76,7 @@ class Index extends Component
             'cms_type' => $validated['cmsType'],
             'wp_username' => $validated['cmsType'] === 'wordpress' ? $validated['wpUsername'] : null,
             'wp_app_password' => $validated['cmsType'] === 'wordpress' ? $validated['wpAppPassword'] : null,
+            'api_instructions' => $validated['apiInstructions'],
         ]);
 
         $this->resetForm();
@@ -97,6 +102,7 @@ class Index extends Component
         $this->cmsType = 'custom';
         $this->wpUsername = '';
         $this->wpAppPassword = '';
+        $this->apiInstructions = null;
         $this->resetValidation();
     }
 }
diff --git a/app/Models/Site.php b/app/Models/Site.php
index c26a0c6..a852374 100644
--- a/app/Models/Site.php
+++ b/app/Models/Site.php
@@ -18,5 +18,6 @@ class Site extends Model
         'cms_type',
         'wp_username',
         'wp_app_password',
+        'api_instructions',
     ];
 }
diff --git a/database/migrations/2026_07_22_140106_add_api_instructions_to_sites_table.php b/database/migrations/2026_07_22_140106_add_api_instructions_to_sites_table.php
new file mode 100644
index 0000000..f9e5ec3
--- /dev/null
+++ b/database/migrations/2026_07_22_140106_add_api_instructions_to_sites_table.php
@@ -0,0 +1,28 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::table('sites', function (Blueprint $table) {
+            $table->text('api_instructions')->nullable()->after('wp_app_password');
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::table('sites', function (Blueprint $table) {
+            $table->dropColumn('api_instructions');
+        });
+    }
+};
diff --git a/resources/views/livewire/sites/index.blade.php b/resources/views/livewire/sites/index.blade.php
index c21f917..3d07897 100644
--- a/resources/views/livewire/sites/index.blade.php
+++ b/resources/views/livewire/sites/index.blade.php
@@ -34,6 +34,8 @@
                                     {{ $revealedId === $site->id ? 'Hide' : 'Show' }}
                                 </button>
                             </div>
+                        @elseif ($site->api_instructions)
+                            <div class="text-xs text-gray-500" title="{{ $site->api_instructions }}">Has API instructions</div>
                         @endif
                     </td>
                     <td class="p-3 text-right space-x-2">
@@ -89,6 +91,13 @@
                         <input type="text" wire:model="wpAppPassword" class="w-full border rounded p-2">
                         @error('wpAppPassword') <span class="text-red-600 text-sm">{{ $message }}</span> @enderror
                     </div>
+                @else
+                    <div>
+                        <label class="block text-sm font-medium">API Instructions (optional)</label>
+                        <p class="text-xs text-gray-500 mb-1">Notes for posting here via this site's own API — auth method, endpoints, payload shape, etc. Read by whoever (agent or you) ends up publishing to it.</p>
+                        <textarea wire:model="apiInstructions" rows="4" class="w-full border rounded p-2"></textarea>
+                        @error('apiInstructions') <span class="text-red-600 text-sm">{{ $message }}</span> @enderror
+                    </div>
                 @endif
 
                 <div class="flex justify-end gap-2">
diff --git a/tests/Feature/Api/SitesApiTest.php b/tests/Feature/Api/SitesApiTest.php
index e434686..bba7cba 100644
--- a/tests/Feature/Api/SitesApiTest.php
+++ b/tests/Feature/Api/SitesApiTest.php
@@ -46,3 +46,15 @@ test('it includes WordPress fields in the site response', function () {
         ->assertJsonPath('data.wp_username', 'admin')
         ->assertJsonPath('data.wp_app_password', 'abcd 1234 efgh 5678');
 });
+
+test('it includes api_instructions in the site response', function () {
+    $site = Site::factory()->create([
+        'cms_type' => 'custom',
+        'api_instructions' => 'POST to /api/publish with a bearer token from .env',
+    ]);
+
+    $response = $this->getJson("/api/sites/{$site->id}");
+
+    $response->assertOk()
+        ->assertJsonPath('data.api_instructions', 'POST to /api/publish with a bearer token from .env');
+});
diff --git a/tests/Feature/Livewire/SitesTest.php b/tests/Feature/Livewire/SitesTest.php
index 186394b..269722c 100644
--- a/tests/Feature/Livewire/SitesTest.php
+++ b/tests/Feature/Livewire/SitesTest.php
@@ -121,3 +121,24 @@ test('switching a WordPress site to a non-WordPress cms_type clears its credenti
         ->wp_username->toBeNull()
         ->wp_app_password->toBeNull();
 });
+
+test('a custom site can be created with api_instructions', function () {
+    Livewire::test(Index::class)
+        ->set('name', 'Custom Site')
+        ->set('url', 'https://custom.example.com')
+        ->set('cmsType', 'custom')
+        ->set('apiInstructions', 'POST to /api/publish with a bearer token from .env')
+        ->call('save');
+
+    $site = Site::where('name', 'Custom Site')->first();
+
+    expect($site->api_instructions)->toBe('POST to /api/publish with a bearer token from .env');
+});
+
+test('editing a site loads its api_instructions', function () {
+    $site = Site::factory()->create(['cms_type' => 'custom', 'api_instructions' => 'Use the /publish endpoint']);
+
+    Livewire::test(Index::class)
+        ->call('edit', $site->id)
+        ->assertSet('apiInstructions', 'Use the /publish endpoint');
+});
diff --git a/tests/Feature/SiteModelTest.php b/tests/Feature/SiteModelTest.php
index 6c9b7ff..ac925a1 100644
--- a/tests/Feature/SiteModelTest.php
+++ b/tests/Feature/SiteModelTest.php
@@ -50,3 +50,20 @@ test('a site can be created as WordPress with credentials', function () {
         ->wp_username->toBe('admin')
         ->wp_app_password->toBe('abcd 1234 efgh 5678');
 });
+
+test('a custom site can store free-text api_instructions', function () {
+    $site = Site::create([
+        'name' => 'Custom Site',
+        'url' => 'https://custom.example.com',
+        'cms_type' => 'custom',
+        'api_instructions' => 'POST to /api/publish with a bearer token from .env',
+    ]);
+
+    expect($site->fresh()->api_instructions)->toBe('POST to /api/publish with a bearer token from .env');
+});
+
+test('api_instructions defaults to null', function () {
+    $site = Site::create(['name' => 'My Blog', 'url' => 'https://example.com']);
+
+    expect($site->fresh()->api_instructions)->toBeNull();
+});