Create the GitHub repo and push

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

Annotations cover the open-world/safety profile (openWorldHint=true, destructiveHint=false), so the description's job is to add context — and it does: it discloses the auth requirement and the idempotent behavior when the repo is already the folder's origin. It doesn't describe what happens on partial failure or conflicting remotes, keeping it from a 5.

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 dense sentences, front-loaded with the command shape, then prerequisites, then the idempotency case. No filler, though the CLI syntax is somewhat cryptic for a reader without gh knowledge.

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 4-param mutation tool with no output schema, the description covers prerequisites, effect, and repeat-run behavior adequately; annotations supply the safety profile. Only minor gaps remain, such as remote/owner handling on partial failures.

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 coverage is 50%: dir and name are documented in the schema, visibility has an enum, and description is undocumented. The description maps visibility to the CLI --public|--private flags but adds no format or constraint detail beyond the schema, so the baseline 3 applies.

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+resource (create a GitHub repo) and even shows the underlying CLI invocation, so the effect is unambiguous. It doesn't explicitly contrast itself with siblings like git_commit or publish_package, but the action is distinct enough to be selected correctly.

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?

Prerequisites are stated ('Needs a commit and a GitHub login'), which is real usage context, and the re-run case is described. However, no alternatives or when-not-to-use conditions are named, so the agent gets context but not routing guidance.

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