render_board

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

Annotations already declare readOnlyHint=false, idempotentHint=true, destructiveHint=false, and the description adds context that it reads the board file from disk and returns the rendered image. However, it does not clarify that rendering writes a PNG file to disk (the reason readOnlyHint is false) or note the default output location, which the schema covers instead.

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?

Two compact sentences, front-loaded with the core action and output. "Reads the board file on disk" is slightly redundant given the schema's board_path description but still clarifies the input source.

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?

There is no output schema, and the description adequately conveys the return (the image itself). However, for a 6-parameter tool with only 33% schema coverage, it leaves the rendering options (side, quality, dimensions) unexplained, so it is not fully 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?

Schema description coverage is only 33% — side, width, height, and quality are undocumented, and the description adds no semantics for any of these. With low coverage the description should compensate for the missing parameter meaning, but it does not.

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?

States a specific verb (Render), resource (the board), output format (3D PNG via kicad-cli), and delivery method (returns the image). An agent can distinguish this from sch_render since it operates on the board rather than the schematic.

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?

"so you can look at it" implies a visual-inspection use case, but there is no explicit when-to-use guidance and no sibling named as an alternative (e.g., sch_render for schematics). Usage is only implied.

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