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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower, yet the description still adds real context: the Pro Authorization token requirement and the fact that Pro items include full source files in structuredContent.files. It does not describe error behavior for a missing or ambiguous id.

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?

Purpose is front-loaded in the first clause, and the two trailing sentences about structuredContent and auth are useful rather than filler. The middle field enumeration is long but each item signals retrievable content, so it mostly earns its space.

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?

With no output schema, the description carries the return-value burden and does so by naming structuredContent.api and structuredContent.files, which is exactly what an agent needs. It is slightly incomplete on failure modes (unknown id, id/kind conflict) but otherwise sufficient for a 2-parameter read tool.

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% and both parameters are documented with examples (button, date-picker, signup-form) plus the enum for kind, so the schema does the heavy lifting. The description adds only the vague 'one component or block' framing, which does not meaningfully extend the schema's 'only needed when an id exists as both'.

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 with scope ('Get full documentation for one Arc component or block') and enumerates exactly what the payload contains. The 'one' scope implicitly separates it from list_components and search_components, so an agent can route without opening the 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?

Usage is implied: call this once you already know a specific id, otherwise use search_components/list_components. However, the description never states when to prefer this tool over its siblings, nor what happens if the id is unknown or ambiguous — the 'kind' param hints at ambiguity but no guidance is given.

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