vast_create_companion

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only states 'Create', which implies a write operation, but fails to mention permissions, idempotency, whether the companion is associated with an ad or creative, or any return values. This is insufficient for a create operation.

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?

The description is a single concise sentence that is not tautological and conveys the core purpose. However, it is perhaps too spare, missing valuable context that could be added without harming conciseness.

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?

Given no annotations, no output schema, and a create operation, the description is minimally complete. It fails to explain what a VAST companion is, how it relates to other entities (e.g., linear creatives or ads), or what the response will contain. This leaves significant gaps for an agent deciding whether and how to invoke the tool.

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 parameter descriptions are clear ('Companion name', 'Companion width in pixels'). The tool description itself adds no extra meaning beyond the schema, which is acceptable given the baseline of 3 for full coverage, but it does not compensate for any ambiguity about units or required fields.

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?

The description uses a specific verb ('Create') and resource ('VAST companion'), making the basic action clear. However, it does not distinguish itself from the similarly named sibling tool 'vast42_create_companion', so the agent cannot tell which API variant to use from this description alone.

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?

There is no guidance on when to use this tool versus alternatives such as vast42_create_companion, nor any context about prerequisites or relationships to other VAST entities like ads or creatives. The agent is left to infer usage solely from the tool name.

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