pyxel-mcp

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explains that the tool captures the screen and analyzes colors, which implies read-only behavior, but doesn't specify if it requires specific permissions, has side effects, or details about error handling. It mentions default values for parameters, which is helpful, but lacks information on rate limits, performance characteristics, or what happens if the script fails.

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 appropriately sized and front-loaded, starting with a clear purpose statement followed by bullet points for parameters. Every sentence adds value: the first explains the tool's function, and the parameter descriptions provide essential context without redundancy. There's no wasted text, making it efficient and easy to parse.

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 the tool's moderate complexity (3 parameters, no annotations, but with an output schema), the description is fairly complete. It covers the purpose, parameters, and implied behavior, though it could benefit from more behavioral details like error handling. Since an output schema exists, it doesn't need to explain return values, which helps. However, without annotations, some safety or operational context is missing.

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 description adds significant meaning beyond the input schema, which has 0% description coverage. It explains that 'script_path' is for a '.py script to run', 'frames' is the 'Frame number to analyze' with a default, and 'timeout' is the 'Maximum seconds to wait for the script' with a default. This clarifies the purpose and usage of all three parameters, compensating well for the lack of schema descriptions.

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 specific action ('Analyze color usage and contrast'), the target resource ('Pyxel screenshot'), and the detailed outputs ('reports which of Pyxel's 16 colors are used, their distribution, background color, and potential contrast issues'). It distinguishes itself from siblings like 'inspect_screen' or 'capture_frames' by focusing specifically on color palette analysis rather than general screen inspection or frame capture.

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 provides no guidance on when to use this tool versus alternatives like 'inspect_screen' or 'capture_frames'. It mentions what the tool does but doesn't specify scenarios where color analysis is preferred over other inspection methods, nor does it mention prerequisites or exclusions. The context is implied through the tool's name and description but lacks explicit usage instructions.

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