pyxel-mcp

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions that the tool 'returns multiple images' and has a timeout parameter, which adds some context. However, it lacks details on critical behaviors like error handling, file output formats, permissions needed, or whether it modifies any state, leaving significant gaps for a tool with no annotation coverage.

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 well-structured and front-loaded, starting with the core purpose, followed by return values, usage context, and parameter details in a bullet-like format. Every sentence adds value without redundancy, making it efficient and easy to scan.

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 no annotations and no output schema, the description provides a good foundation with purpose, usage, and parameter semantics. However, it lacks details on output behavior (e.g., image format, storage location), error cases, and how it integrates with sibling tools, making it incomplete for a tool with 4 parameters and complex functionality like animation verification.

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%, so the description must compensate. It adds meaningful semantics by explaining each parameter: 'script_path' as an absolute path to a .py script, 'frames' as comma-separated frame numbers with a default, 'scale' as a screenshot scale multiplier, and 'timeout' as maximum seconds to wait. This provides clear context beyond the bare schema, though it could specify formats (e.g., image types) more explicitly.

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 purpose: 'Capture screenshots at multiple frame points for animation verification.' It specifies the verb ('capture'), resource ('screenshots'), and context ('animation verification'), making it easy to understand. However, it doesn't explicitly differentiate from sibling tools like 'play_and_capture' or 'run_and_capture', which prevents a perfect score.

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 implied usage guidance by stating it's 'useful for verifying animations, transitions, and time-based effects,' which gives context for when to use it. However, it doesn't explicitly mention when not to use it or name alternatives among the sibling tools, such as how it differs from 'compare_frames' or 'play_and_capture'.

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