github_repos

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states 'List GitHub repositories', which implies a read-only operation, but doesn't specify any behavioral traits like authentication requirements, rate limits, pagination, or what data is returned (e.g., repo names, details). This is a significant gap for a tool with no annotation coverage.

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 extremely concise with just three words ('List GitHub repositories'), which is front-loaded and wastes no space. For a simple tool with no parameters, this brevity is efficient and appropriate, 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?

Given the tool's simplicity (0 parameters, no output schema), the description is incomplete. It lacks context on behavior (e.g., authentication, scope), usage guidelines, and output details, which are crucial for an agent to invoke it correctly. With no annotations to compensate, the description should provide more completeness for effective tool selection.

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 has 0 parameters with 100% coverage, so the schema fully documents the lack of inputs. The description adds no parameter information, which is appropriate since there are no parameters to explain. This aligns with the baseline expectation for zero-parameter tools, where minimal description suffices.

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 'List GitHub repositories' clearly states the verb ('List') and resource ('GitHub repositories'), making the basic purpose understandable. However, it doesn't distinguish this tool from potential siblings (like 'github_file') or specify scope (e.g., user vs. organization repos), leaving it somewhat vague. It avoids tautology by not just restating the tool name.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention any context, prerequisites, or exclusions, such as whether it lists public vs. private repos or requires authentication. Given the sibling tools include 'github_file', there's no differentiation, leaving the agent to guess based on tool names alone.

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