list_repositories

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

With no annotations provided, the description carries the full behavioral burden, but it only states that this tool lists repositories and can fall back to GITHUB_OWNER. It does not disclose pagination behavior, authentication requirements, whether only public repositories are returned, or the response shape, especially with no output schema present.

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, front-loaded sentence with no wasted words. The core action and key scoping decision are stated immediately, making it easy for an agent to parse quickly.

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 six-parameter tool with no annotations and no output schema, the description is too thin to be contextually complete. It does not explain what the response looks like, that results are paginated, how the default owner is resolved, or what behavioral expectations an agent should hold beyond the schema.

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 all six parameters (page, sort, type, owner, per_page, direction) documented and enums enumerated. The description adds no meaning beyond what the schema already provides, so the baseline of 3 is appropriate.

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 repositories') and the resource scope ('for a specified owner (user or organization), or the default GITHUB_OWNER'), making the tool's purpose immediately recognizable. It is distinguishable from siblings like get_repository_details or search_repositories, though it does not explicitly name or contrast those alternatives.

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?

There is no explicit guidance about when to use this tool versus search_repositories, get_repository_details, or other siblings. The only contextual signal is the owner-scoping phrase, but no exclusions, prerequisites, or alternative-selection conditions are provided.

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