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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower; the description goes beyond them by disclosing what each mode returns (durations, resolutions, aspect_ratios, audio_toggle, credits), what the 'defaults' mean, and when max_prompt_length appears. The trailing credit-consumption note concerns generate_video rather than this read tool, slightly diluting the added value.

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 core purpose and return contents; the field enumeration is informative rather than redundant. The final sentence about credits being consumed when generating is tangential to a get tool and is the one line that does not clearly earn its place.

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 carries the return-value burden and does so adequately by enumerating the per-mode fields and explaining the defaults and the conditional max_prompt_length. The missing piece is argument semantics for 'model', which keeps it from being complete.

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 0% for the single required 'model' parameter, and the description does not compensate: it never states what form the argument takes (model ID, name, slug) or how to discover valid values. A read-only lookup keyed on an undocumented identifier is a real gap.

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 ('Get full capabilities and credit pricing for one video model'), which clearly separates it from the batch-oriented list_video_models and from generate_video. It stops short of explicitly naming a sibling to route against, so it lands at 4 rather than 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 phrase 'for one video model' implies this is the single-model detail lookup versus the list variant, but there is no explicit when-to-use or when-not-to-use guidance, nor any prerequisite such as where to obtain a valid model identifier.

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