create_branch

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

No annotations are provided, so the description must fully disclose behavior. It only states the basic creation action and source, but omits critical details such as permissions required, failure modes (e.g., if the branch already exists), and side effects. It does not even explicitly say this is a write operation, aside from the verb 'Create'.

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 a single, focused sentence that front-loads the action and key details, followed by a documentation link. There is no redundant or extraneous information.

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?

While the schema fully covers parameters, the tool has no annotations or output schema, and the description is minimal. It adequately explains the core action and source but lacks context about side effects, error conditions, or prerequisites. For a mutation tool, more transparency would be needed to be fully complete.

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 already documents all four required parameters with descriptions, achieving 100% coverage. The description adds no new parameter semantics beyond what the schema provides, so it meets the baseline but does not exceed it.

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 ('Create'), the resource ('a new branch in a GitHub repository'), and the source ('from an existing branch or commit SHA'). This specificity distinguishes it from sibling tools like delete_branch or list_branches, making the purpose unambiguous.

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 tool's use case is implied by its name and description, but there is no explicit guidance on when to use it versus alternatives (e.g., create_or_update_file) or any exclusions. It does not mention that branches should not be created from refs/heads/ or any other constraints beyond the schema.

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