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

Annotations already declare a non-read-only, non-idempotent, open-world, non-destructive operation, so the safety profile is covered. The description adds genuinely useful context by noting credit consumption, but says nothing about it being a long-running/async job, what identifying handle comes back, or whether credits are refunded on failure.

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?

Two tight sentences, front-loaded with the core operation and followed by the cost-relevant detail. No filler, no restatement of the title.

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 and an async, credit-consuming job tool, the description should tell an agent what comes back (a job id) and how to follow up (get_job, cancel_job). The duration precondition and credit note are present, but the calling-and-chaining cycle is left undocumented.

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 the baseline would be 3; the description adds a small amount of value by anchoring the source to a long video of at least a minute. It adds no meaning beyond the schema for source_id, video_url, instructions or target_duration.

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 ('Condenses a long video ... into a short highlight montage of its best moments') with a clear input precondition (at least 1 minute). It does not distinguish itself from plausible neighbors such as create_ai_clips or export_clips, so it stops short of a 5.

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 minimum-length precondition and the note that credits are consumed imply when the tool applies, but there is no explicit when/when-not and no named alternative for the cases this tool does not fit (e.g. short clips or AI clip generation). Usage must be inferred.

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