git_diff

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

Annotations already declare readOnlyHint/idempotentHint/non-destructive, so safety is covered. The description adds a genuinely useful behavioral trait the annotations cannot convey: 'Large diffs are truncated,' which warns the agent that output may be incomplete and should be scoped with path. No auth or rate-limit context, but truncation disclosure is meaningful 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 sentences, no filler, with the default-mode scoping front-loaded and the truncation caveat last. Every clause earns its place.

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 described. The description covers default mode, the staged variant, and the truncation risk, which is nearly everything an agent needs — the only real gap is any explanation of the `path` parameter's purpose.

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?

With 0% schema description coverage, the description must carry parameter meaning. It explains `staged` well (default false, true selects the index), but says nothing about `path`, leaving half of the parameters undocumented in both schema and 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?

States a specific tool and resource (git diff) plus its default operating mode, which lets an agent distinguish it from git_status/git_log without reading the schema. However, it never explicitly contrasts itself with those siblings, so it stops short of full differentiation.

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 parenthetical 'unstaged by default; set staged=true for index' gives a clear condition for choosing each mode, which is real usage guidance. It offers no exclusions or named alternatives (e.g., when to prefer git_status or git_log instead), so it is clear context rather than full when/when-not guidance.

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