list_labels

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

The description explains the return format (JSON array with id, name, color, description) and implies a read-only operation. While annotations are absent, the description adequately communicates the tool's behavior for a simple listing. It does not mention potential limits or authorization, but the context is clear.

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 with three well-structured sentences. Front-loads the usage context, then specifies return format, requirements, and see-also references. No extraneous words.

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 list tool with no output schema, the description fully explains the return type and fields, meeting the agent's needs for using the tool. It also references related tools. However, it omits potential pagination or error scenarios, though these might be unnecessary for this simple endpoint.

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 input schema already provides 100% coverage for both parameters ('owner' and 'name') with descriptions. The description merely restates that these are required, adding no new semantics beyond the schema.

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 identifies the tool's purpose: viewing available labels for a repository. It specifies the action ('list'), the resource ('labels'), and the context ('before applying them to issues'). It also distinguishes from sibling tools by referencing create_label and update_issue.

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 ('before applying labels to issues'), what parameters are required ('owner' and 'name'), and provides alternative tools ('create_label, update_issue'). This gives clear guidance for correct usage.

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