list_usd_file_formats

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

Annotations already declare the safe read-only, idempotent profile, so the bar is lower. The description still adds real value: it guarantees the always-returned native and supported sets, and discloses the side effect that include_descriptions triggers a call to AddUsdImportFileFormatDescriptions to populate description strings.

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?

Front-loads the core purpose, then adds the return contract in a compact structured block. Sentences are dense but each earns its place; only minor verbosity from the inline example.

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 supplies the full return shape (native_formats, supported_formats, counts, optional descriptions). A single fully-documented parameter plus this return contract leaves nothing an agent needs 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 100%, so baseline is 3. The description goes beyond it by explaining exactly what include_descriptions produces, giving a concrete example ('usdc; Universal Scene Description binary files'), and noting the plugin-extension case ('abc' from usdAbc).

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 ('List') and resource ('USD file format extensions the engine supports') precisely. It is clearly distinguishable from all siblings, which deal with USD stages, prims, layers, variants and attributes rather than format extensions.

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 it is useful (discovering supported USD import extensions) but never states when to use it versus alternatives or when-not to use it. Since there is no sibling tool covering the same resource, no explicit alternative is named, leaving usage to inference.

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