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

Annotations indicate readOnlyHint=false and destructiveHint=false, so the write nature is implied but the description adds that it returns the full updated/created object and describes Space scoping behavior. This goes beyond the annotations by clarifying the return value and override option.

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 succinct sentences cover the action, role examples, return value, and Space scoping, with zero redundancy. Every clause provides useful information.

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 output schema, the description compensates by stating the return type ('full updated/created object'). Space scoping is clearly explained. Nested objects are acknowledged with a pointer to the OpenAPI spec, which is acceptable since the most important behavioral and scoping details are covered.

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 schema provides enum values for role and a pattern for space_id, but the description enhances understanding by giving concrete role examples and explaining that space_id overrides the active Space for one call. The body schema says to see OpenAPI spec for nested shapes, which is reasonable since the core fields are already named.

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 ('attach') with a clear resource ('asset to a campaign') and adds role examples (MARKETING_IMAGE, LOGO). It differentiates from siblings like attach_asset_to_ad and detach_asset_from_campaign via the explicit 'campaign' scope.

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 states the tool is scoped to the active Space and directs users to set_active_space or pass space_id to override, providing clear context for when to use this versus other space-related tools. It doesn't explicitly mention alternatives like attach_asset_to_ad, but the naming makes the campaign vs ad distinction obvious.

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