vast_update_placement

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

No annotations are provided, so the description must disclose behavior itself. It only says 'update' without explaining whether omitted fields are preserved or reset, whether this is a partial or full update, or what the response will be. For a mutation tool with 14 parameters, this is a significant gap.

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 sentence with no redundant wording, making it concise. However, it is underspecified for a tool of this complexity; it lacks front-loaded context beyond the basic verb+resource statement.

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?

For a complex 14-parameter tool with no output schema and no annotations, this description is inadequate. It doesn't clarify whether the update is partial or full, what the return value is, or how fields like zone and channel interact (mutual exclusivity). The schema covers parameter definitions but not the operational context.

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?

The input schema documents all 14 parameters with descriptions (100% coverage), so the baseline is 3. The tool description adds no parameter-level detail beyond what the schema already provides, not even confirming the update behavior (e.g., partial updates).

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 clearly states the action ('Update') and resource ('existing VAST placement'), distinguishing it from create/delete operations. However, it doesn't differentiate among sibling update tools like vast42_update_placement or draft_update_placement, so it lacks sibling differentiation.

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 description provides no guidance on when to use this tool versus alternatives such as vast_create_placement, vast_get_placement, draft_update_placement, or vast42_update_placement. There are no exclusions, prerequisites, or selection criteria.

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