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

The description goes well beyond the annotations by disclosing the read-then-write race condition: a slot open at read time may be taken before the write lands. It also documents the default 14-day window, the 60-day cap, and the account-ambiguity handling requirement, which are important behavioral traits an agent would not otherwise know.

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 definition is front-loaded with the use case and the sibling contrast, and most sentences carry real information. It is somewhat long and repeats schema details such as ISO 8601 formatting, the 14-day default, and the 60-day cap, which could be trimmed, but it avoids filler.

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?

Given the presence of an output schema and rich annotations, the description is complete for this tool's complexity. It covers purpose, alternatives, date-window behavior, race-condition risk, and account-selection procedure, so an agent has everything needed to invoke it 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 schema already documents from/to as ISO 8601 with their defaults and the 60-day maximum. The description adds value by tying those parameters to the default-window behavior and by giving explicit guidance on accountId: ask the user which account to use rather than selecting one automatically when list_accounts returns multiple accounts.

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 ('returns the account's schedule over a date window as concrete dated entries') and explicitly differentiates itself from the sibling tool list_timeslots by contrasting dated occupancy entries with recurring weekly rules. An agent can tell exactly what this tool does and how it differs without opening either schema.

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 triggering questions ('what is on their Pinterest schedule', 'when their next opening is', 'how full their queue looks') and a clear when-not-to-use rule: do not read an open entry and pass its time back as sendAt. It names the correct alternative workflow (useNextOpenSlot with create_post/schedule_post) and includes an account-selection prerequisite when multiple accounts exist.

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