ads_google_ads_pmax_replace_images

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

With no annotations, the description carries the burden well: it discloses the safe-swap ordering ('New images are linked first'), what is not touched (square images, logos, text), and a confirmation gate. It stops short of stating whether the old landscape/portrait images are unlinked or deleted, and mentions no permission or rate-limit constraints.

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 sentences, mutation behavior first, preservation guarantees second, prerequisite last. Nothing is redundant and nothing could be removed without losing information.

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 destructive-ish mutation with no annotations and no output schema, the behavioral story is solid, but the missing guidance on customer_id/login_customer_id and on the fate of replaced images leaves real gaps an agent needs before calling it correctly.

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 5 parameters, so the description must compensate and largely does not. It covers the asset group, the asset payload, and confirm=true, but leaves customer_id vs login_customer_id, file_path format, label, and the per-item field_type semantics unexplained beyond the self-evident enum.

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 (Replace) on a precise resource (landscape and portrait marketing images in a Performance Max asset group). The scope is bounded to 'enabled' images, so an agent knows exactly what this touches without opening the schema, and no sibling tool competes for this operation.

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 delimits usage by scope ('enabled landscape and portrait marketing images') and adds a hard prerequisite ('Requires explicit confirm=true'), but never explicitly says when to prefer this over other flows or what happens when an asset group has no such images. Usage is implied rather than spelled out.

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