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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the workspace scope and the team-based narrowing behavior, which is useful context beyond the annotations, but it doesn't describe return format, pagination, or other runtime details. That is acceptable for a simple read-only list tool.

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?

A single, well-structured sentence that front-loads the main purpose and appends the optional narrowing condition. There is no filler or redundant detail.

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 read-only list operation with one optional parameter, the description plus annotations and schema cover what an agent needs to select and call the tool. There is no output schema, but the return value is clearly implied by 'list labels'. It doesn't mention pagination or ordering, but these are minor for this tool's complexity.

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 schema already documents the single optional 'team' parameter with 100% coverage, so the baseline is 3. The description reiterates the narrowing behavior ('narrowed to the ones a team can use') but doesn't add significant new semantics beyond what the schema 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 names a specific verb ('List'), a clear resource ('labels'), and a scope ('available in the workspace'), with an optional team narrowing. This distinguishes it from label mutation tools like create_label, update_label, and delete_label without needing to open schemas.

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 clearly states the tool's context: listing workspace labels, optionally filtered by team. It doesn't explicitly enumerate when not to use it or name alternatives, but the read-only intent and optional team parameter make the usage context clear enough for a tool with no competing label-listing sibling.

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