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

Annotations already declare destructiveHint=true, idempotentHint=true, and openWorldHint=true, so the bar is lower. The description adds useful context about the moderation flow and points existing-live-artwork changes to a separate portal workflow, but it never discloses what this call destroys or overwrites, and the 'existing artwork → portal' line arguably undersells the destructiveHint. Idempotency is covered only by the schema's idempotency_key field, not the prose.

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 core action front-loaded, followed by timing and the alternative workflow. No filler, though the middle sentence could be merged and the jargon slightly reduces scannability.

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?

An output schema exists, so return values need not be explained, and annotations carry much of the safety profile. However, for a destructive, open-world mutation with a nested file object, the description omits permissions/auth needs, what moderation entails, and what happens to prior artwork, leaving real gaps.

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 67%, so the schema already documents advertisementId and idempotency_key. The description adds nothing about parameters and leaves the nested creativeFile object's four sub-properties (file_id, file_name, mime_type, download_url) undescribed in both places, which is a gap for a nested input. Baseline 3 is appropriate given partial schema coverage.

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 states a specific verb and resource: 'Copy a user-selected creative file into the native campaign asset and moderation flow.' This distinguishes it from sibling read/booking tools like get_campaign_status or prepare_campaign_booking, though the phrase 'native campaign asset and moderation flow' is jargon that a first-time agent must interpret.

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?

It gives clear timing guidance ('Attach artwork before booking') and routes a specific case away ('Existing live artwork changes follow the portal replacement workflow'). It stops short of naming a sibling tool or stating prerequisites (e.g., campaign must exist in draft), so it is strong context but not fully explicit when/when-not routing.

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