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

Adds substantial context beyond the annotations: required permissions (mcp.assets.refresh, allow_pull), the customer_not_owned error for out-of-tenant accounts, quota/time budget behavior, and the empty-vs-needs_sync reading rule. 'No Google mutation' clarifies that refresh is local, consistent with destructiveHint=true referring to the local snapshot rather than Google state. It could still say more about what the local refresh destroys/overwrites.

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?

Single dense paragraph, front-loaded with the purpose and scope before the operational caveats. Sentences like the error-code and permission clauses earn their place, though the run-on packaging of quota, permissions, downstream reads, and empty semantics is heavier than needed.

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 write-to-local tool with no output schema and 2 undocumented params, the description covers most of what an agent needs: scope, permissions, quota, error behavior, and downstream read targets. The one gap is connection_context, which is neither in the schema nor the description.

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 coverage is 0%, so the description must carry the parameter burden. It implies customer_ids ('named already-registered accounts', out-of-tenant returning customer_not_owned) but gives no format or limit guidance, and never mentions connection_context at all. Partial compensation only.

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 (Pull) plus exactly what is pulled: structure, daily and entity metrics, and the creative inventory. It immediately scopes the resource to 'named already-registered accounts only (no account discovery)', distinguishing it from discovery/list siblings, so an agent can identify it without opening the schema.

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?

Clear when-to-use context: named already-registered accounts, no discovery, then read google_ads_insights_query_daily or the overview afterward. It also names the quota/time-budget constraints and the empty-vs-needs_sync interpretation. It does not explicitly contrast itself with the sibling google_ads_accounts_sync, which is the closest alternative, so the routing is slightly incomplete.

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