diff --git a/README.md b/README.md
index ff566a9..0119179 100644
--- a/README.md
+++ b/README.md
@@ -203,6 +203,7 @@ Example: full manifest
 {
   "$schema": "https://open-plugins.com/schemas/1.0.0/plugin.schema.json",
   "name": "plugin-name",
+  "icon": "./icon.png",
   "version": "1.2.0",
   "description": "Brief plugin description",
   "author": {
@@ -235,6 +236,7 @@ If a required field is missing, has the wrong type, is empty, or otherwise viola
 
 | Field         | Type     | Description                                                           |
 | ------------- | -------- | --------------------------------------------------------------------- |
+| `icon`        | string   | Plugin icon image: a plugin-relative path (§4.1) or an absolute `https:` URL. See §5.7. |
 | `version`     | string   | Version string (Semantic Versioning RECOMMENDED). Used for update checks and cache freshness. |
 | `description` | string   | Short description of plugin purpose.                                  |
 | `author`      | object   | Author object with optional `name`, `email`, and `url` string fields. |
@@ -268,6 +270,17 @@ Invalid names: `My-Plugin` (uppercase), `-start` (leading hyphen), `has--double`
 
 The optional `extensions` field contains client-specific manifest data keyed by extension namespace. See §8 for processing rules.
 
+### 5.7 Icon
+
+The optional `icon` field is a string identifying an image that represents the plugin in host user interfaces. If present, its value MUST be either:
+
+1. a plugin-relative path as defined in §4.1 (beginning with `./` and resolving within the plugin root), or
+2. an absolute `https:` URL that contains no user information and no fragment.
+
+The image SHOULD be square and at least 512x512 pixels. Whether a host retrieves and renders the icon is host-defined, and a host MAY ignore `icon` entirely. Hosts MUST NOT retrieve a remote icon while loading a plugin (see §5.2).
+
+If `icon` is present but is neither a valid plugin-relative path nor a valid absolute `https:` URL, or if a plugin-relative path resolves outside the plugin root, the host MUST ignore the `icon` field and MUST continue loading the plugin. The `icon` field is advisory only; its value or validity MUST NOT affect component discovery or execution.
+
 ## 6. Component discovery
 
 > **See also:** [§4 Plugin package model](#4-plugin-package-model) for directory layout conventions.
diff --git a/schemas/1.0.0/plugin.schema.json b/schemas/1.0.0/plugin.schema.json
index 99b095e..37dc75f 100644
--- a/schemas/1.0.0/plugin.schema.json
+++ b/schemas/1.0.0/plugin.schema.json
@@ -58,6 +58,10 @@
       "additionalProperties": {
         "type": "object"
       }
+    },
+    "icon": {
+      "type": "string",
+      "description": "Optional plugin icon image, either a plugin-relative path beginning with './' (resolved within the plugin root) or an absolute https: URL with no user information or fragment. The image SHOULD be square and at least 512x512 pixels. Advisory only; hosts MUST ignore an invalid value and MUST NOT retrieve a remote icon while loading a plugin."
     }
   },
   "required": ["$schema", "name"],