List changed files

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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower, and the description adds a genuinely useful behavioral fact the annotations cannot carry: patches are truncated to the first 3,000 characters per file. It does not discuss rate limits or pagination semantics, but the truncation caveat is real added value.

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 with the core behavior front-loaded and the optional patch detail second. No filler, no redundancy with the schema.

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?

An output schema exists, so return-value documentation is unnecessary, and annotations cover the safety profile. The description supplies what remains missing: what the list contains (files with per-file add/delete counts) and the patch truncation caveat.

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 the baseline is 3, but the description goes beyond the schema by explaining what include_patch actually yields (each file's diff) and the truncation behavior the schema does not mention. It does not clarify 'limit' beyond the schema's own description, so it is not a full 5.

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 states a specific verb and resource ('Lists the files a pull request changes') and adds the returned detail ('additions and deletions per file'), which is more than the name alone conveys. It does not explicitly distinguish itself from siblings like get_pull_request, but the file-level scope is concrete enough for an agent to select it.

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?

There is no explicit when-to-use guidance, no prerequisites, and no mention of alternatives such as get_pull_request for PR metadata. The only conditional advice concerns include_patch, which is parameter usage rather than tool-selection guidance.

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