Retrieve a movie's cover image by providing its movie ID and filename. Get the specific artwork file for any movie in Radarr.
Read MediaCover.
GET /api/v3/mediacover/{movieId}/{filename}
Args: movie_id: Path parameter. filename: Path parameter.
| Name | Required | Description | Default |
|---|---|---|---|
| filename | Yes | ||
| movie_id | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations accurately indicate read-only, idempotent, and non-destructive behavior, so the description adds little. It does not disclose that this returns binary image data rather than JSON, which is a critical behavioral aspect not covered by annotations. The description only repeats the endpoint, providing minimal additional context.
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 description is short and front-loaded with the verb, but it spends two lines redundantly listing the path parameters that are already in the schema. Acceptable length but not fully justified.
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?
Given that the tool has an output schema (likely binary or image response), the description does not explain what it returns or how to use the response. It is incomplete for an agent to understand the tool's purpose and output nature.
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 0%, meaning the schema does not document any parameters. The description only echoes 'Path parameter' for each, giving no semantics about what movie_id or filename mean, acceptable formats, or how to obtain them. This is insufficient for correct invocation.
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 says 'Read MediaCover' but fails to explain what MediaCover represents (e.g., movie poster or fanart) and the role of movie_id and filename. It is little more than a restatement of the endpoint. The verb 'Read' is generic, and the resource is ambiguous.
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 guidance on when to use this tool versus the many sibling get_* tools. It does not mention that this is for fetching image files, how to determine the filename, or any prerequisites. The agent is left to guess based on the tool name.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.