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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false, so the write-but-idempotent profile is structured. The description reinforces this with 'Reuse idempotencyKey' and adds a compliance constraint, but it omits what happens on a duplicate save, permission requirements, and effect on the saved-ads collection. Adequate against a lower annotation burden.

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 tight sentences, front-loaded with the core action and free of filler. The idempotency reminder is slightly redundant with the annotation but still useful for the caller.

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 described, and the idempotency/compliance notes are present. However, for a mutating save tool it still leaves gaps around prerequisite permissions and the behavior of duplicate saves, which an agent would want before invoking it.

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 0% across four parameters, so the description must carry the load. It implicitly covers note ('optional notes') and idempotencyKey ('Reuse idempotencyKey'), but adId and brandId are left entirely unexplained, leaving half the parameters undocumented anywhere.

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?

States a specific verb+resource: save a selected public ad as inspiration for this brand, with optional notes. The purpose is clear, though it does not explicitly distinguish itself from siblings like analyze_library_ad, get_library_ad, or save_intelligence_item.

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 when-to-use guidance or named alternative. It implies a search-then-save workflow and adds a compliance caveat ('do not copy the advertiser's claims or creative'), but nothing tells the agent when this tool is the right choice versus get_library_ad, analyze_library_ad, or save_intelligence_item.

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