structured_diff

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

With no annotations, the description carries the full behavioral burden and does so well. It discloses that both files are treated read-only, that the diff is computed without Word, and that per-change detail is capped at detail_cap on huge diffs while counts remain complete. It also enumerates the full range of returned information.

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 dense but every clause earns its place: core purpose, output components, cap behavior, sibling distinction, and read-only safety. It is front-loaded with the main action and the alternative tool, making the most important routing information immediately visible.

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?

For a complex diff tool with no annotations, the description covers what it returns, when to use it versus the sibling, the detail cap behavior, and the read-only safety profile. The presence of an output schema further reduces the need for the description to explain return value structure. Nothing critical is missing.

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 0%, so the description must compensate. It explicitly clarifies detail_cap's behavior ('Per-change detail is capped at detail_cap entries on huge diffs'), which goes beyond the schema. old_path and new_path are only implied by 'both documents' and their schema names, leaving a small gap in explicit parameter documentation.

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 opens with a specific verb and object ('Diff two saved drafts agent-readably') and enumerates the precise output categories, so the agent knows exactly what the tool does. It also explicitly contrasts itself with com_compare_documents ('Deliberately NOT a redline'), distinguishing it from a closely related sibling.

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 gives an explicit when-not-to-use rule: 'use com_compare_documents for a Word-rendered tracked-changes comparison.' It also states that the tool is read-only and computed without Word, which gives clear context for safe invocation among the large sibling toolset.

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