pyxel-mcp

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

With no annotations provided, the description carries full burden and does well by disclosing key behaviors: it runs scripts without starting game loops, auto-detects durations (0 = auto-detect), has timeout defaults, and returns specific analysis data (note sequence with timing, frequency, volume). However, it doesn't mention potential side effects like file creation or resource usage.

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 with purpose statement upfront, followed by behavioral context, then detailed parameter explanations. Every sentence adds value, though the Args section formatting could be slightly more concise.

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 complexity (5 parameters, audio rendering/analysis functionality) and the presence of an output schema (which handles return values), the description provides complete context: clear purpose, parameter semantics, behavioral details, and differentiation between sound vs music rendering modes.

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?

With 0% schema description coverage, the description fully compensates by explaining all 5 parameters in detail: script_path requirements (absolute path), sound_index range (0-63) and interaction with music_index, duration_sec behavior (0 = auto-detect), timeout purpose, and music_index significance (>=0 triggers music rendering). This adds substantial meaning beyond the bare schema.

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 ('Render a Pyxel sound or music to WAV and return waveform analysis'), identifies the resource (Pyxel sound/music), and distinguishes it from siblings by focusing on audio rendering and analysis rather than visual inspection or game execution.

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 clear context about when to use sound_index vs music_index ('Ignored when music_index is set', 'When set (>=0), renders the full multi-channel music mix instead of a single sound'), but doesn't explicitly mention when to use this tool versus sibling tools like play_and_capture or run_and_capture.

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