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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds value by explaining that the source is immutable and that for private projects the owner's OAuth is required. It does not contradict annotations and adds practical context about capability-based access.

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 consists of three concise sentences, each adding essential information: definition, use case, and access details. No extraneous words; well-structured and front-loaded with the core purpose.

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 47 sibling tools (many mutations), the description fully covers when and how to use this read-only fetch tool. With an output schema present, return values need no further explanation. The description covers usage, access, and verification purpose completely.

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% with descriptions for both parameters. The description adds meaning by specifying that slug and version come from open_in_studio and that slug acts as a capability for public projects, exceeding what the schema alone provides.

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 verb ('Fetch'), resource ('exact immutable .kcad source and parameters'), and context ('captured at a prior `open_in_studio` version'). It distinguishes this tool from siblings by focusing on read-after-write verification of a specific revision.

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 explicit usage guidance: 'Use this to read-after-write verify a release' and details how to pass slug and version. It also explains access requirements for public vs private projects, covering when and for whom the tool is appropriate.

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