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

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=false, so safety is covered; the description adds genuinely new context beyond that – server-side scoping to channel_pid=tiktokglobal_int, cross-channel data sharing with Meta, and the semantics of the `adset` field (AppsFlyer source field mapping to TikTok's ad_group role, not a Meta ad set). No pagination or rate-limit behavior is disclosed.

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?

Front-loaded with what is read, then REQUIRED, optional breakdown, a clarifying caveat, and an example – the labelled structure makes it skimmable. Slightly dense and the Meta-sharing sentence is tangential, but no sentence is pure filler.

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 read-only, no-output-schema tool it adequately describes the returned metrics and required inputs, including a working example. The missing pieces are the undocumented cursor (implying pagination that is never described) and connection_context, which leaves a small gap in an otherwise complete definition.

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%, so the description carries the burden; it meaningfully explains product_id, event_name, and the five breakdown options, and clarifies the adset mapping. However cursor and connection_context are never mentioned, leaving two of five parameters undocumented anywhere.

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 (read) and resource (AppsFlyer count, unique-user, revenue aggregate for one saved product and event) with explicit scope ('today', server-scoped to channel_pid=tiktokglobal_int). It does not name the nearest sibling mmp_insights_query_product_event_summary, so an agent must infer the today-vs-summary distinction from the tool name rather than the description.

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?

Gives clear prerequisites and provenance: product_id comes from products_list (product_ref) and event_name from products_get_actions, with a labelled EXAMPLE invocation. It never states when to prefer this over the sibling summary tool or any exclusion, so guidance is strong on 'how' but silent on 'when not'.

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