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

Annotations already establish readOnlyHint/idempotentHint/non-destructive, so the safety profile is covered. The description goes further by disclosing the polling cadence, the stop condition, the fields returned at each stage, and the exact auth mechanism (OAuth or Bearer acd_live_ key). This is meaningful operational context well beyond the annotations, though it doesn't describe terminal error/failure states.

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 purpose and return contents, followed by polling guidance and then the auth block; each sentence carries distinct, actionable information. The credential sentence is long but is genuinely required context, so waste is minimal.

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 an output schema present, return-value documentation is not strictly required, yet the description still summarizes the payload. Combined with the polling policy and full auth instructions, an agent has everything needed to call this correctly on a post-generate_ad workflow.

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 the single job_id parameter is already documented as 'returned by generate_ad'. The description does not add format or constraint detail beyond that, 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 and resource ('Check an ad job') and then enumerates exactly what it surfaces: stage, percent, finished video URL, storyboard sheet, duration, size and credits charged. This clearly distinguishes it from generate_ad and the list/get_generation siblings without needing to open either schema.

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 routes the agent: 'Poll every 15 seconds after generate_ad; stop after 15 minutes.' It names the predecessor tool and the exact polling policy, so there is no ambiguity about when and how often to call it.

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