git_diff

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

With no annotations, the description carries the burden of conveying behavioral traits. It implies a read-only operation via 'show,' but does not disclose details like default behavior (unstaged vs. staged changes), return format, or any side effects. It adds minimal context beyond the obvious, so a moderate score is warranted.

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, concise sentence that front-loads the core function. It contains no wasted words and is easy to parse.

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?

Despite having an output schema, the description is incomplete regarding what this tool can actually do. It claims to show changes 'between commits, working tree, or index,' but the schema only offers boolean toggles for staged and stat_only, with no way to specify arbitrary commit ranges. This omission makes the description misleading about the tool's true capabilities. It also leaves out default behavior (e.g., unstaged changes by default).

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%, with each parameter (staged, file_path, stat_only) having a clear description. The tool description adds no additional meaning about the parameters, but since the schema already fully documents them, the baseline of 3 is appropriate.

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 tool's function: 'Show changes between commits, working tree, or index.' It uses a specific verb ('show') and resource ('changes'), and it distinguishes from siblings like git_log and git_status by focusing specifically on diffs.

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 when to use the tool (to view changes between various states), but it does not explicitly state when to use it over alternatives like git_log or git_status, nor does it mention any exclusions or prerequisites. The usage context is clear enough for a simple diff tool, but lacks explicit guidance.

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