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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds one piece of context annotations cannot convey — the paid-plan/connected-account prerequisite — but says nothing about response shape, rate limits, or what happens when no accounts are connected.

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?

It is a single run-on sentence with a long parenthetical metric list, so it is dense but not front-loaded — the key fact (project-level rollup across connected accounts) sits before the enumeration while the plan requirement is buried at the end. Nothing is actively wasteful, but the flat structure makes scanning harder than it needs to be.

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?

With no output schema, the description must carry the return-value burden, and the metric enumeration does help an agent anticipate what comes back. However, it gives no sense of nesting/structure, units, empty-state behavior, or how the 'best and worst posts' are ranked, which leaves real gaps for a complex aggregate tool.

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 50%: 'days' only says 'Default 28' (with min 1 / max 40 enforced in schema) and 'project' has no description at all. The description's phrase 'for the last days' vaguely gestures at the window but adds no default value, unit semantics, or explanation of what 'project' accepts (name vs. id), so it does not compensate for the coverage gap.

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 names a specific resource — aggregated stats for the project's connected accounts — and enumerates the concrete metrics returned (views, likes, comments, shares, saves, followers, best/worst posts, watch time). It never states a verb and does not distinguish itself from siblings like get_video_stats or get_report, so an agent must infer the aggregation level from the metric list alone.

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?

Usage is only implied: 'the last days' hints at the days parameter, and 'Paid plans with connected accounts' states a prerequisite. There is no explicit when-to-use, no when-not-to-use, and no routing to alternatives such as get_video_stats for per-video data or get_best_times for timing questions.

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