list_branches

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

With no annotations, the description carries the full burden of behavioral disclosure, but it only says 'List branches in a repository.' It does not disclose pagination behavior, that it returns a page of results by default, or any details about ordering or rate limits. The behavior is implied to be a read operation, but no additional transparency is provided.

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 concise and front-loaded with the purpose, followed by an Args list. There is no fluff or irrelevant content. The structure is clean and easy to scan, though the parameter descriptions are redundant with the schema's property names.

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 list tool with an output schema and no annotations, the description is sparser than expected. It does not explain pagination semantics, default values from the schema, or provide any guidance on when to choose this tool over siblings. The return value is presumably covered by the output schema, but the lack of usage and behavioral context leaves the description incomplete.

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 0%, so the description must compensate. It lists each parameter with a minimal gloss ('owner: Repository owner', etc.), which adds a little beyond the schema's bare titles. However, it does not explain semantic details like page indexing, per_page limits, or that owner/repo are required, leaving the agent with only minimal information.

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 and resource: 'List branches in a repository.' It is unambiguous about what the tool does, and the owner/repo parameters make the target resource clear. However, it does not explicitly differentiate itself from sibling tools like list_tags or _list_releases, which are similar list operations on the same repository.

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 does not mention that it is for listing branches specifically (though implied by the name), nor does it give any conditions, exclusions, or context for selection. There is no discussion of pagination, default behavior, or when another tool might be more appropriate.

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