github_pulls_get_diff

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

Annotations already declare readOnly, openWorld, and idempotent, so safety is covered. The description adds meaningful behavioral context beyond annotations: the entire diff comes in one call, there is no pagination or size-limiting control, and it is the same endpoint as `pulls_get` with a different representation. It does not discuss rate limits or authentication, but for a read-only diff tool that is a minor omission.

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?

Three tight sentences, front-loaded with the primary purpose and then the key alternative. Every sentence earns its place by adding either scope, comparison, or limitation.

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?

No output schema exists, but the description states the return format (unified diff) and discloses the critical no-paging limitation. Combined with the fully covered input schema and safety annotations, an agent has everything needed to call the tool correctly.

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% and all three required parameters are documented in the schema. The description adds no parameter-level syntax or meaning beyond what the schema already provides, so 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?

States a specific verb ('Get') and resource ('a pull request's whole change as a unified diff'), and explicitly distinguishes itself from siblings `pulls_get` (same endpoint, different representation) and `pulls_list_files` (for large changes needing paging). An agent can tell exactly what this tool returns versus its alternatives.

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?

Explicitly states when to use it ('read a change end to end') and when to use the alternative (`pulls_list_files` when the change is large enough to need paging), including the reason ('this has no way to ask for less'). No inference is required.

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