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

Annotations already establish read-only/idempotent/non-destructive, and the description adds behavior the annotations cannot: the 62-day cap on ranges, the default 14-day window, the warning that a delayed post is unconfirmed and must not be resent, and the composite result shape (one post with multiple per-account targets, each with its own status and eventual public URL). This is meaningful context beyond the structured safety hints.

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 primary purpose is front-loaded and every clause about selection modes earns its place. The closing sentence on multi-account targets and public URLs leans toward output-format detail that the output schema already covers, making the description slightly longer than strictly necessary.

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 5-parameter, zero-required query tool with an output schema, the description supplies everything needed to call it correctly: all modes, mutual exclusivity, defaults, range limits, and the caution against resending delayed posts. Return-value explanation is appropriately delegated to the output schema.

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 full burden, and it does: it defines what post_id, from/to (ISO times, max 62 days apart), drafts:true, and attention:true each select, plus the no-parameter default. The vague 'attention' flag is given a precise three-part definition, which the schema alone would leave entirely opaque.

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 opens with a concrete verb+resource ("Read the social calendar") and then enumerates the exact selection modes, so an agent immediately knows this is a read tool over scheduled/social posts. It does not name or contrast against any sibling (e.g. schedule_post or list_generations), so it falls short of full sibling differentiation.

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 when-to-use guidance for every mode: post_id for one post, from/to for a range, drafts:true for unscheduled posts, attention:true for failed/stuck/reconnect-needed posts, and the default (next 14 days) when nothing is passed. The "Pass exactly one of" constraint removes ambiguity about combining parameters.

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