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

The description adds value beyond annotations by detailing that it fetches the full .kcad source and metadata, that updating the same slug live updates the user's open tab, and that private projects require OAuth. Annotations already declare readOnlyHint and destructiveHint, so the description complements them without contradiction.

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 is four sentences long, each providing unique information. It could be slightly more concise, but it is well-structured and front-loaded with the main 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 tool's dual mode (fetch vs list) and dependencies (OAuth, output structure), the description covers essential context. The presence of an output schema reduces the need to describe return values, so the description is adequately 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?

With 100% schema description coverage, the baseline is 3. The description adds context about the slug's origin (from a listing or /p/<slug> link) and the behavior when omitted, which is helpful but not extensive.

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 it fetches a specific project or lists saved projects, distinguishing between the two modes based on the slug parameter. It directly addresses the verb 'get' and the resource 'project', and provides specific use cases like reopening a saved project or browsing.

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 explicitly states when to use the tool (to reopen a saved project or browse saved projects) and provides context about OAuth requirements for private projects and listing mode. While it doesn't explicitly mention when not to use it or list alternatives, it gives clear guidance on usage.

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