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

Annotations already declare this is a non-read-only, non-destructive, non-idempotent, closed-world operation, so the safety profile is covered. The description adds genuinely new context by stating the "'creator' scope" authorization requirement and noting the new campaign object with its id is returned. It does not warn that retries create duplicates (relevant given idempotentHint=false), which is the main remaining 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?

Three short sentences with the purpose stated first, then the usage trigger, then the return value and auth requirement. Nothing is padded and no sentence is redundant with the point of being noise.

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 two-parameter create with a 100% coverage schema, an output schema, and full annotations, the description covers purpose, trigger, return, and auth scope. The return-value sentence is somewhat redundant given the output schema, and there is no guidance on duplicate creation or campaign limits, so it is strong but not exhaustive.

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% with only two flat parameters, so the schema already explains name and description fully. The description restates "optional brief and goals," which maps loosely to the description field but adds no syntax, limits, or format guidance beyond the schema.

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 opens with a specific verb+resource ("Create a new campaign workspace") and adds scope detail (optional brief and goals), so an agent will not confuse it with update_campaign, get_campaign, or list_campaigns. It stops short of naming any sibling explicitly, so it lands just under the top mark.

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?

"Use when the user wants to start a new initiative, project, or campaign" gives a clear positive trigger with concrete user-intent phrasing. There is no explicit exclusion or alternative-path guidance (e.g., when to update an existing campaign instead), which keeps it from a 5.

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