docker_read_image

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the burden. It adds useful behavioral context by specifying the output is an MCP image and that common raster formats are supported, implying other formats may fail. However, it does not disclose error handling, size limits, whether the container must be running, or that the operation is non-destructive (though 'Read' implies it). This is adequate but lacks depth.

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 two sentences, front-loaded with the core action and output type. The second sentence adds meaningful constraint about supported formats. Every word contributes value; there is no redundancy or fluff.

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?

For a simple 2-parameter read tool, the description is nearly complete. It states the purpose, output type, and format support, which is sufficient for an agent to select and invoke it. Minor gaps include lack of explicit error behavior or unsupported format handling, but the tool's simplicity and the output statement make it adequately complete.

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?

The input schema already provides clear descriptions for both parameters (path: 'Absolute or relative path inside the container', container: 'Docker container name or id'), achieving 100% coverage. The tool description does not add any additional parameter-specific meaning beyond what the schema states, so the baseline score of 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?

The description clearly states the tool's function: 'Read a file from a Docker container and return it as an MCP image.' The verb 'Read' is specific, the resource is a file in a Docker container, and the output type (MCP image) is explicitly defined. It distinguishes itself from sibling docker_read_file by specifying image output and raster format support.

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: it is for reading image files from a container and returning them as MCP images, especially when the file is in a raster format. However, it does not explicitly state when to use this tool versus docker_read_file or other siblings, nor does it provide any exclusions or alternative recommendations.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.