list_pull_files

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

With no annotations, the description fully handles behavioral disclosure. It describes pagination ('Paginated (page 1-based, limit <= 100)') and lists the fields in each entry, setting clear expectations for output. No mention of errors or edge cases, but for a read-only list tool, this is adequate.

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?

Three sentences, all essential. No waste, front-loaded with purpose, followed by pagination info, output fields, and usage guidance. Efficient structure.

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?

No output schema, so description carries responsibility for explaining return values. It lists all relevant fields (`filename`, `status`, `additions`, etc.) and explains pagination. Does not cover possible empty results or error cases, but sufficient for typical use.

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 100%, so baseline is 3. The description mentions `index` in context and pagination parameters, but adds no new details beyond what the schema provides (e.g., defaults for repo and owner are already in schema). Marginal added value.

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?

Specifically states 'List the files changed in one pull request by its `index`', clearly identifying the verb and resource. Differentiates from siblings like list_pull_commits and get_pull_request by focusing on file changes.

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?

Explicitly says 'Use to understand a PR's diff scope before reviewing or merging', providing clear usage context. Does not explicitly state when not to use or list alternatives, but the context is well-defined.

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