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

Beyond the readOnlyHint/destructiveHint/openWorldHint annotations, the description discloses the scoring methodology, the three possible `basis` values, the 15-post threshold that switches behavior, the audience-online blending limited to Instagram and TikTok Business, the `audience_online` response field, and the required analytics:read scope. This is unusually rich behavioral disclosure for a read tool.

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?

The core purpose and output shape are front-loaded in the first clause, and the fallback/scope information follows in a logical order. It is dense and some computation internals ('recency-weighted and outlier-damped') are arguably more than needed, but nearly every sentence carries actionable information.

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 carries the burden of describing returns and does so ('top 3 recommended slots plus a per-day breakdown'), plus the basis values and fallback counts. An agent has everything needed to call and interpret the result correctly.

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 100%, so the baseline is 3, but the description adds real meaning: `platform` determines whether audience-online blending applies (only Instagram and TikTok Business) and `timezone` governs how buckets are computed. It goes beyond restating the schema.

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 states a specific verb and resource ('Get recommended posting times (day + hour) for one platform') and immediately scopes it to workspace posting history. It is clearly distinguishable from the analytics siblings (get_account_analytics, get_analytics_overview), which return metrics rather than recommendations.

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 explicitly names the trigger ('Use this before scheduling when the user asks "when should I post?" or hasn't specified a time'), which functions as both when-to-use and an implicit when-not. It does not name a competing tool, but no sibling actually competes for this job, so the guidance is close to complete.

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