wordpress_upload_mediaUpload an image or file to the WordPress media library by providing a base64-encoded file and filename.
Upload image or file to WordPress media library (provide base64 encoded file)
| Name | Required | Description | Default |
|---|---|---|---|
| fileBase64 | Yes | ||
| filename | Yes |
Changes observed during successful MCP inspections.
v1.0.0Input schema / $schemaAdded value: +"http://json-schema.org/draft-07/schema#"Input schema / additionalPropertiesAdded value: +falseDoes the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. It discloses that the tool accepts base64-encoded files, a key input requirement, and implies a write operation to the media library. However, it does not mention permissions, file size limits, or whether duplicates are created, which are material behavioral traits for a mutation tool.
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?
The entire description is a single, fifteen-word sentence that efficiently conveys the core purpose and a critical usage detail. There is no fluff, repetition, or irrelevant material, making it highly scannable for an AI agent.
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?
The tool has no output schema and no annotations, so the description should ideally explain return values and potential failure modes. It does neither. The description also omits practical constraints like supported file types or authentication prerequisites, leaving the agent to guess at the operation's full effects.
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?
Given 0% schema coverage, the description must compensate. It adds value by noting 'base64 encoded file', clarifying the expected format for fileBase64. However, it leaves filename semantics unexplained (e.g., extension, naming conventions) and does not provide guidance on encoding generation, so it only partially bridges the schema gap.
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?
The description clearly states the action ('Upload') and the resource ('WordPress media library'), making the tool's purpose unambiguous. It distinguishes itself from siblings like 'get_media' or 'update_media' by focusing on the creation of a new library entry. The mention of 'image or file' also defines the input scope.
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?
The description implies usage for adding new media to the library, but it lacks explicit guidance on when to choose this over alternatives. No exclusions or alternative tool references are provided, leaving the agent to infer that 'upload' means creating rather than updating or deleting. This implied context is helpful but not explicit.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.