Update WordPress media metadata such as title, alt text, caption, and description for a specific media item.
Update media item metadata (title, alt text, caption)
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | Media ID | |
| alt | No | Alt text | |
| site | Yes | Site id (see list_sites) | |
| title | No | Title | |
| caption | No | Caption | |
| description | No | Description |
Changes observed during successful MCP inspections.
v3.4.0Input schema / properties / siteAdded value: +{
+ "description": "Site id (see list_sites)",
+ "type": "string"
+}Input schema / requiredPrevious value: -[
- "id"
-]New value: +[
+ "site",
+ "id"
+]v2.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden, yet it only says what fields exist. It never states whether this is a partial update (are omitted fields left untouched?), what permissions are needed, or whether changes are reversible. For a mutation tool this is a significant gap.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
A single front-loaded sentence with no filler. It is efficient, though its brevity borders on under-specification rather than tightness.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
A 6-parameter mutation tool with no annotations and no output schema needs the description to explain update semantics (partial vs full), prerequisite lookup, and result shape. One parenthetical field list is far short of what is required.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so all six parameters are already documented in the schema. The description echoes three of the editable fields (title, alt, caption) but omits 'description' and the required identifiers 'site'/'id', adding little beyond the schema. Baseline 3 applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb (Update) and resource (media item metadata) and names the mutatable fields (title, alt text, caption). However, the sibling list contains both mcp_update_media and wp_update_media, and the description gives no basis for choosing between these near-duplicates.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
No when-to-use guidance, no prerequisites, and no mention of the competing wp_update_media sibling or mcp_get_media/mcp_list_media for locating an item first. An agent gets no routing help at all.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.