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

Annotations already declare destructiveHint=true and idempotentHint=true, so the safety profile is covered. The description still adds real value by disclosing partial-update semantics ('Only non-null fields are updated') and that advertisement_faqs replaces the entire list — but it stays silent on whether other list fields (tags, language) replace or merge, and on any permission or validation requirements, which matters for a destructive 17-param mutation.

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 dense sentences, front-loaded with the verb and resource, then key semantics. Nothing is redundant, though the parenthetical about customer identifiers interrupts the flow slightly.

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 17-parameter destructive mutation with no output schema and 0% schema coverage, the description leaves too much open: collection-field merge behavior, datetime format, accepted type/language values, and what the call returns or whether it can be undone.

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%, so the description carries the full burden, yet it explains only the four identifier parameters and the FAQ entry shape. The remaining fields — title, note, sort, tags, type, group, poster, country, options, language, and both datetimes — get no semantics, format, or replace-vs-merge clarification.

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 and resource ('Edit fields of an existing advertisement') plus how the target is located by id or uuid. It is clear on its own, but it never distinguishes itself from adjacent siblings such as update_advertisement_keys, publish_advertisement, or edit_article, so differentiation is left to the caller.

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?

Usage is implied by 'existing advertisement' and the lookup keys, and the non-null semantics tell the agent it is a partial update. However, there is no explicit when-to-use/when-not guidance and no named alternative for changing keys or publishing, which are distinct sibling operations on the same resource.

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