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

Annotations already declare readOnly/idempotent/non-destructive, so those add nothing. The description earns credit by disclosing the blocking behavior of wait (~50 s) and the shape of the result payload, which annotations cannot express. No auth or rate-limit context, but the wait semantics are the key behavioral trait here.

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-loaded with the resource, then the return payload, then the wait modifier and endpoint. The parenthetical field list is somewhat dense but each item is informative. No filler sentences.

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 steps in to describe the result object (video/image with url, cover, size, length, workId) and notes how to view the cover. Combined with the wait semantics, an agent has enough to call and interpret the result, though account-scoping via email is left to the schema.

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%, so the schema already documents all three parameters including wait and email. The description's 'wait: true waits up to ~50 s' largely restates the schema's own description, adding no new syntax or constraints. Baseline 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?

Names the specific resource (a Kling task) and enumerates what is returned: status, ETA, and results with url/cover/size/length/workId. The verb 'get' is implied by the title and the GET endpoint note. It's clearly distinct from kling_list_tasks or kling_delete_task, though it never names those siblings.

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?

Usage is implied: retrieve a task by id, optionally waiting for completion. The 'wait: true waits up to ~50 s' note gives real operational context for polling. However, there is no explicit 'use this instead of kling_list_running when...' routing or when-not guidance.

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