github_git_refs_create

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

Annotations already declare readOnlyHint=false and openWorldHint=true, so the agent knows this is an open-world write. The description adds the meaningful constraint that the target must be an existing commit and that the ref must be fully qualified, but it says nothing about what happens on conflict (existing ref) or required write permissions.

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 tight sentences, zero waste, with the core action front-loaded and the input constraint immediately following. Nothing redundant or padded.

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 simple 4-parameter mutation with no output schema, the description covers the action, the target, and the key input constraint, and the annotations carry the safety profile. It could be more complete by noting conflict/error behavior, but the essentials are present.

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 all four parameters are already documented, including the 'refs/heads/my-branch' format for `ref`. The description merely restates the fully-qualified requirement that the schema already carries. Baseline 3 applies since the schema does the heavy lifting.

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 gives a specific verb+resource ('Create a branch or tag pointing at an existing commit'), which is clear and distinct from the read-only sibling github_git_refs_get. It does not, however, explicitly name any sibling or contrast itself with adjacent tools like github_repos_create_or_update_file, so it stops short of a 5.

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?

Usage is only implied: an agent infers you call this when you need a new branch or tag. There is no explicit when-to-use or when-not guidance, no mention of checking for pre-existing refs (github_git_refs_get), and no exclusions.

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