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

Beyond the annotations (idempotent, non-destructive, open-world), the description discloses non-obvious behaviour: PDF writes to 'path' when given (a side effect), otherwise returns base64, requires the uniwire[pdf] extra, and the hosted server returns pdf_url instead. That local-vs-hosted split is genuinely useful context an agent cannot infer from annotations alone.

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?

Front-loaded with the core action, then organized parameter-by-parameter. It does repeat some schema content (the enum values for kind and color), but the density of useful detail keeps it efficient overall.

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 eight parameters, file-writing behaviour and hosted/local divergence, the description covers what an agent needs to invoke it correctly. An output schema exists, so return values needn't be explained, though the SVG/PDF return notes are a helpful bonus. Missing only explicit sibling routing.

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 coverage is 100%, so the baseline is 3. The description earns a step up by adding meaning the schema lacks: view is tied to a wire-marking view id, SVG returns every sheet or a specific 1-based 'sheet', PDF's path/base64/pdf_url branching, and the colour legend and IEC 60445 convention.

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?

Opens with a specific verb and resource: 'Draw the electrical diagram (schéma unifilaire / multifilaire)'. The agent knows exactly what output this produces, distinct from validation/normalisation siblings. It doesn't explicitly name a sibling to contrast with, which keeps it just below a 5.

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?

Usage is only implied: you call this when you want a diagram. There is no explicit guidance on when to prefer this over viewer_link or when a diagram is not appropriate, and no prerequisites or exclusions are stated.

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