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

Annotations only provide generic false hints, and the description adds some context: bulk support and keyword field structure. It does not disclose partial_failure behavior, status defaults, or response/error semantics, leaving limited behavioral transparency.

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 concise sentences front-load the core purpose, then present the keyword format, then mention bulk capability. No filler or redundant restatement.

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 mutating tool with 8 parameters and no output schema, this is incomplete: no return value, no explanation of partial_failure, and the bulk mention creates ambiguity about whether ad_group_id is still required when ad_group_ids is used.

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?

With 0% schema description coverage, the description must compensate, but it only documents keyword text/match_type/cpc_bid and names ad_group_ids/customer_ids. It leaves ad_group_id, customer_id, status, account, and partial_failure unexplained, so parameter coverage is insufficient.

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?

Description clearly states 'Add positive keywords to an ad group' with a specific verb, resource type, and target. It naturally distinguishes from siblings like google_ads_negative_keyword_add and keyword update tools.

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 implies use for adding positive keywords and notes bulk execution via ad_group_ids and customer_ids. However, it never explicitly contrasts with the negative keyword tool or explains when to use single vs. bulk fields.

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