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

With no annotations, the description carries the full burden, and it does disclose a non-obvious behavior: the tool inspects Post Type and media URL to choose a platform-specific format (YouTube short vs video, LinkedIn video vs feed, Instagram reel). It says nothing about whether this publishes immediately or queues, what happens if Post Type is unset, or whether the operation is reversible.

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?

Two short sentences, front-loaded with the core action, with zero filler. The second sentence is telegraphic and slightly hard to parse, but it is dense rather than verbose.

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 scheduling mutation with no annotations and no output schema, the definition covers the format-selection logic but omits the essentials an agent would want: where the schedule date/time comes from (there is no such parameter), failure modes, and whether social accounts must already be linked.

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 single parameter has 100% schema description coverage, so the baseline of 3 applies. The description never mentions notification_message or its fallback-reply role, adding no meaning beyond 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?

States a specific verb and resource ("Schedule one calendar row on Nova"), and the word "one" implicitly separates it from schedule_all_calendar_rows. It doesn't name that sibling or unschedule_calendar_row explicitly, so differentiation is inferred rather than stated.

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 mention that Post Type is "set via update_calendar_row" implies a prerequisite step and points at the right sibling to run first. However, there is no explicit when-to-use/when-not guidance, no reference to schedule_all_calendar_rows for bulk work, and no stated preconditions such as a connected social account.

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