Get shape library

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered; the description adds the return content (style syntax and shape names) and the behavioral rule that names must be exact and never guessed. It does not mention caching, rate limits, or whether results vary by version, but the added context is substantial.

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 critical instruction is front-loaded in the first sentence, and the library list is compactly grouped by category rather than prose. Every line is load-bearing reference data with no filler.

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?

No output schema exists, so the description carries the burden of explaining what comes back ('style syntax and shape names'), which it does. Combined with the enumerated library values and the timing instruction, an agent has everything needed to invoke this correctly.

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 100% schema coverage the baseline is 3, but the description goes well beyond the schema's single example by enumerating every valid library value grouped by domain (aws4, azure2, cisco19, bpmn, etc.). Since the schema has no enum, this list is the only authoritative source of accepted inputs and directly prevents invalid calls.

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 and resource ('Get the style syntax and shape names of a draw.io icon library') and makes clear it is a lookup/discovery tool, not a drawing tool. An agent can distinguish it from siblings like get_drawing_guide or create_new_diagram without opening any schema.

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?

Gives an explicit trigger and ordering constraint: 'Call this BEFORE drawing with cloud, network or other icon shapes, and use the exact names it returns; never guess them.' That is a clear when-to-use plus an anti-pattern to avoid, though it does not name an alternative tool for non-icon shapes or say when this call is unnecessary.

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