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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is covered. The description does add real behavioral detail — a blank string clears the product-card link — which is a non-obvious destructive side effect. It still says nothing about what happens to fields omitted from payload, whether updates are partial or full replacement, or permission requirements.

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?

Two sentences, front-loaded with the action and then the one non-obvious parameter rule. No filler, no restatement of the tool name.

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 explained, but this is a destructive mutation with a free-form payload object and zero schema descriptions. Covering a single optional string parameter leaves an agent unable to call it confidently without guessing at payload shape and required-field semantics.

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 6 parameters, so the description must carry the full semantic load, and it documents only product_ref. The required template_id and name, the free-form nested payload object, template_type, and the connection_context pattern are all left completely unexplained.

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?

The description states a specific verb and resource: 'Update a reusable Google ad template.' That is enough to distinguish it from read-only siblings like google_ads_templates_list or google_ads_template_delete, but it never contrasts with google_ads_template_save (the likely upsert/create counterpart), which is the ambiguity an agent will actually hit.

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 only conditional guidance ('when product cards are enabled') concerns how to pass one parameter, not when to choose this tool over google_ads_template_save or the reverse_engineer variant. There is no statement of prerequisites, when-not-to-use, or the alternative to pick instead.

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