List GitLab project labels

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

Annotations declare readOnlyHint=true, destructiveHint=false, and idempotentHint=true, so the description doesn't need to repeat safety info. It adds a tiny bit of context by stating 'available in a GitLab project', but doesn't disclose pagination behavior, whether it includes ancestor groups by default, or any rate limits. Given the annotations cover safety, a 3 is appropriate.

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 a single, concise sentence that states the purpose without fluff. It is front-loaded and every word adds value. Perfectly sized for a simple listing operation.

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?

The tool has 5 parameters with only one documented in the schema, and no description of return values (although an output schema exists which helps). The description doesn't cover the meaning of 'include_ancestor_groups' or 'search' behavior. For a listing tool with this complexity, the description is under-specified but not critically incomplete given the self-explanatory parameter names and the output schema presence.

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 description coverage is only 20% (only 'project' has a description), leaving 'page', 'search', 'per_page', and 'include_ancestor_groups' without descriptions in the schema. The tool description does not elaborate on these parameters either, so it doesn't compensate for the low coverage. However, parameter names are self-explanatory (e.g., 'search' implies filtering, 'per_page' implies pagination size), so some meaning is inferable. Baseline of 3 is fair.

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 action (list) and resource (labels in a GitLab project). It differentiates from sibling tools by specifying 'project labels' and the project context, distinguishing it from list_group_projects, list_group_members, etc. However, it doesn't explicitly contrast with list_project_members or other project-specific listing tools, though the label-specific resource is clear enough.

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 implies usage when you need to retrieve labels for a specific project, but provides no explicit guidance on when to use this vs alternatives like list_group_labels (not present) or when not to use it. It lacks context on prerequisites (e.g., project must exist) or typical scenarios like filtering issues by labels. Adequate but minimal.

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