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

Annotations already cover read-only, idempotent, open-world and non-destructive behavior, so the bar is lower; the description still adds ordering semantics (saved voices first, then official), the returned fields, and the underlying endpoint. It omits pagination or result-size limits, but a simple list endpoint likely has none.

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?

One dense sentence that front-loads the resource and scope, then the result composition, then the endpoint. Nothing is redundant and no clause is wasted.

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?

With no output schema, the description compensates by enumerating return fields (id, name, sample) and ordering. It is essentially complete for a zero-required-param read, with only minor gaps like result size or failure modes when the account is ambiguous.

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% and the single email parameter is fully documented in the schema as required when the token spans several Kling accounts. The description only echoes this with "on one account," adding no syntax or format detail beyond the schema, so baseline 3 applies.

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 resource (the voice list for kling_omni_video v4) and the exact contents returned (id, name, sample) plus ordering. It distinguishes itself by scoping to omni-video v4 voices, though it does not name the near-identical siblings kling_list_tts_voices or kling_list_element_voices.

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 voices for kling_omni_video v4" gives clear context for when to call it — to obtain voice_1..3 ids for omni video. There are no explicit exclusions, so an agent must infer that TTS or element voices live in the other list tools.

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