Get Pull Request Diff Tool

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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description usefully adds the output format ('unified diff'), but it says nothing about a critical trait for diff tools — whether large diffs are truncated, capped, or paginated — nor about auth requirements.

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?

A single front-loaded sentence with zero filler and no redundancy. It is efficient, though its brevity comes at the cost of the usage and behavioral context an agent would benefit from.

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 values need not be explained, and readOnlyHint covers the safety side. However, for a tool whose output can be enormous, the absence of any note on diff size limits or truncation leaves a real gap.

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 100%, so repo, owner, pull_number are all documented in the schema and the description adds no parameter-level detail. Baseline 3 applies when the schema does the heavy lifting.

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 ('Get') and resource ('the unified diff for a GitHub pull request'), which clearly distinguishes it from metadata siblings like get_pull_request_tool. It stops short of explicitly naming or contrasting with any sibling, so the differentiation is inferred rather than stated.

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 guidance on when to choose this over get_pull_request_tool, get_file_content_tool, or list_pull_request_comments_tool, nor any mention of prerequisites. The agent must infer that 'I want the diff' maps to this tool from the name alone.

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