bb_get_pull_request_diffstat

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It accurately conveys that this is a read-only operation returning a per-file summary, which is the core behavior. However, it does not explicitly state the lack of side effects, how the file list is ordered, or whether all files are included or only changed ones. The description is adequate but not detailed enough to fully anticipate edge cases.

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 primary action ('Get the diffstat') and provides only essential details about the output. It is concise without being under-specified, and every word contributes to understanding the tool's purpose.

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?

The tool has no output schema, so the description must hint at what the response contains; it does this by specifying 'per-file summary of lines added/removed and change status.' Given the tool's moderate complexity (6 params, no output schema) and read-only nature, the description covers the essential return structure and operation. It could mention filtering via parameters, but that is already in the schema, so the description is sufficiently complete for most use cases.

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 has 100% description coverage for all six parameters, each clearly documented. The tool description does not add any parameter-specific meaning beyond what the schema already provides, so the baseline of 3 applies. No extra context like default behavior or parameter interactions is offered in the description.

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 precisely states the tool's function: 'Get the diffstat for a pull request' and enriches it with a per-file summary of lines added/removed and change status, which clearly distinguishes it from sibling tools like bb_get_pull_request_diff (full diff) and bb_get_pull_request (PR metadata). The verb 'Get' plus resource 'diffstat' is specific and 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 description implies the appropriate usage context: when you need aggregated, per-file change statistics for a pull request rather than the full diff or detailed PR info. No explicit alternatives are named, but the phrasing provides situational clarity without misleading the agent. Missing explicit exclusion of when *not* to use it, but the stated purpose is clear.

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