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

With no annotations, the description carries the behavioral disclosure burden. It clearly states key behavior: one row per platform target, and an empty list when the post has no analytics yet. It does not cover errors, auth, or failure modes, but the core read behavior is transparent.

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 concise sentences with no filler. The main action is front-loaded, metrics are listed compactly, and the empty-list edge case earns its place.

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 single-parameter tool with no output schema, the description covers normal invocation, return shape, and an important edge case. It omits error behavior for invalid post IDs or permission failures, but nothing essential to a basic correct call is missing.

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?

The description implies that postId identifies a single published post, which adds some meaning beyond the bare schema property. But it never explicitly describes postId, its format, or where to source valid post IDs. Since schema description coverage is 0%, this is only partial compensation.

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 operation ('Fetch'), a clear resource ('per-platform analytics for one published post'), and enumerates the exact metrics returned. This scopes it away from broader siblings like get_analytics_overview or get_content_insights.

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?

It gives explicit user-phrase triggers ('how is my post performing?' / 'show me stats on this post'), so an agent knows when to use it. However, it does not name alternative tools or state when not to use it, so it falls just short of full guidance.

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