get_instance_url

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

With no annotations, the description discloses it's cheap and does not require authentication. It also outlines the two output formats. It lacks details on errors or behavior with an empty instance, but is still informative.

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 concise and front-loaded with the purpose, followed by a brief usage note and parameter details. Every sentence adds value without redundancy.

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?

For a simple tool, the description is fairly complete: it covers purpose, usage context, and parameter specifics. It could mention read-only nature or behavior with missing instance, but overall sufficient given output schema existence.

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?

The description adds significant meaning beyond the schema: it explains the format values ('report' as plain text, 'json' as a JSON object) and clarifies instance is optional. This compensates for 0% schema description coverage.

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 tool returns the base URL of the YouTrack instance. It differentiates from siblings by mentioning it's a cheap, no-auth-state probe useful for renderers, unlike get_current_user.

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?

It explains when to use (for downstream renderers needing URLs without auth) and implicitly contrasts with alternatives like get_current_user. However, it doesn't explicitly state when not to use or list other alternatives.

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