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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds which fields come back (name, status, parent ad set/campaign), which is mildly useful context but no auth, rate-limit, or failure behavior.

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?

A single front-loaded sentence with no filler; the returned-field list is the only detail beyond the core purpose. Nothing is wasted, though it is very terse.

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 simple single-parameter read operation with annotations covering safety and no output schema, the description need not explain return formatting. Naming the fields returned compensates for the absent output schema, leaving only minor gaps around id sourcing.

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 a single required parameter, so the baseline is 3. The description adds no syntax, format, or source guidance for ad_id beyond what the schema already says.

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 ('Get one Meta ad by id') and scopes it to a single record, with a parenthetical naming the returned fields. It implicitly distinguishes itself from the list/get_ad_set/get_campaign siblings by resource, though it never names them.

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 phrase 'by id' implies the tool is for direct lookup when an ad id is already known, but there is no explicit when-to-use, when-not, or pointer to meta_ads_list_ads for discovery. Usage is left to inference.

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