GitHub MCP Server

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

No annotations are provided, so the description carries full burden. It states the basic action but doesn't disclose behavioral traits like pagination behavior (implied by parameters but not described), rate limits, authentication requirements, whether it returns public/private repos based on permissions, or what happens with invalid owners. The description is minimal and lacks operational context.

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?

Extremely concise with just one sentence that states the core purpose. No wasted words or redundant information. The description is front-loaded with the essential action and target. Every word earns its place in this minimal 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 has an output schema (which handles return values) and 100% schema coverage for parameters, the description's minimalism is somewhat acceptable. However, for a listing tool with 5 parameters and no annotations, the description should provide more context about when to use it, authentication needs, and typical workflows. It meets minimum viability but has clear gaps in operational guidance.

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%, so the schema already documents all 5 parameters thoroughly with descriptions, defaults, and constraints. The description adds no additional parameter semantics beyond what's in the schema - it mentions 'user or organization' which maps to the 'owner' parameter but provides no extra context about parameter interactions or usage patterns.

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 verb ('List') and resource ('repositories'), specifying the target as 'for a user or organization'. It distinguishes from siblings like 'search_repositories' by focusing on listing rather than searching, but doesn't explicitly contrast with similar listing tools like 'list_starred_repos' or 'list_user_orgs'.

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?

No guidance on when to use this tool versus alternatives. The description doesn't mention when this tool is appropriate compared to 'search_repositories', 'list_starred_repos', or 'get_repository'. There's no context about prerequisites, authentication requirements, or typical use cases.

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