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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the base safety profile is known. The description adds meaningful behavioral detail: it returns cumulative snapshots and per-day gains for views/likes/comments/shares, and scopes to a single post. This goes beyond what annotations provide, though it stops short of discussing pagination or date-range limits.

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 sentences with no filler: the primary action, the return shape, and the parameter source. The description is front-loaded and every sentence earns its place, with only minor, acceptable redundancy between 'snapshots and deltas' and 'cumulative snapshots and per-day gains'.

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 read-only tool with no output schema, the description tells the agent what ID to pass, where to get it, and what kind of data to expect. It would be slightly more complete if it specified the response structure or ordering, but this is a minor gap for such a simple 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?

The schema already fully documents the only parameter as 'Analytics record ID (from list_analytics)' with 100% coverage. The description repeats this source but adds no new meaning beyond the schema, so the baseline score of 3 is appropriate.

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 clearly states the verb 'Get', the resource 'per-day analytics snapshots and deltas for a single post', and the return contents. It is unambiguous and naturally distinguishes itself from siblings like list_analytics and sync_analytics.

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 description gives clear context: this tool is for per-day analytics of one post, and it tells the agent to source the ID from list_analytics. It does not explicitly name alternative tools or when-not-to-use conditions, but the workflow is well implied.

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