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

Annotations already state readOnlyHint and openWorldHint, so the description doesn't need to repeat that. It adds value by noting the return is a list and that pagination uses a cursor. This goes beyond annotations and clarifies expected behavior 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?

Two concise sentences with no fluff. The core action is front-loaded, and the pagination note is placed at the end. Every word contributes to the tool's description.

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 moderate complexity and full schema coverage, the description is adequate. It mentions returning a list and pagination, which covers the main runtime behavior. No output schema exists, but the return type (list) is stated. The description doesn't enumerate fields, but that's not required when the schema and annotations cover parameters and safety.

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 100%, with each parameter (handle, sort, type, direction, cursor) already documented. The description adds minimal extra semantic value beyond the schema, such as 'use cursor when paginated,' which is already implied by cursor's schema. Baseline 3 is appropriate because the description doesn't need to compensate for missing schema info.

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?

States a specific verb and resource: 'List repositories for a GitHub user or organization.' This clearly distinguishes from sibling tools like github_profile_get, github_profile_activity_list, and github_repositories_get, which have different scopes. The mention of both user and organization covers the handle parameter's flexibility.

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?

Provides minimal guidance on when to use this tool. It says 'Accepts a username' and 'use cursor when paginated,' which addresses input and pagination, but does not explicitly contrast with alternatives like github_profile_activity_list or github_repositories_get. No when-to-use or when-not-to-use conditions are given.

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