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

With destructiveHint=true and openWorldHint=true already declared, the description goes well beyond them: remove is a soft-delete, add/update return a `warnings` field when a post will not go out (stories cap, vacation mode), scheduling can be refused with scheduling_not_available, and the approval semantics of auto/warning constitute the owner's consent. This is exactly the extra behavioral context annotations cannot convey.

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?

It is long but front-loaded with the action enumeration, and most sentences carry operational facts (timezone, slide limits, warning triggers, consent semantics) rather than filler. The approval_mode paragraph is dense but each clause adds a distinct behavior; it could still be tightened slightly.

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 15-parameter, no-output-schema mutation tool the description covers the high-stakes behavior (action semantics, approvals, refusals, warnings, date format) that an agent needs before calling. It remains incomplete on several lower-traffic params (caption_mode, beat_slug, source_asset_id) and does not restate the return shape beyond `warnings`.

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 only 40% across 15 params, so the description must compensate, and it does for the critical ones: it spells out scheduled_date format/timezone/default publish time, the 2-10 carousel slide constraint, all three approval_mode enum meanings, recurrence in update, and days for bulk_fill. Gaps remain for caption_mode, beat_slug, source_asset_id, and video_url, which are undocumented in both places.

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 names a specific verb+resource ('Manage scheduled posts') and then defines each of the four action values distinctly (add creates, update patches, remove soft-delete cancels, bulk_fill generates AI drafts). An agent can tell this apart from read-only siblings like get_schedule or the publish_draft path mentioned inside the text.

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 clear conditional guidance for approval_mode ('Set auto or warning only when the owner asked for it') and names the alternative flow ('pass approval_mode=email to have it wait for the owner's explicit publish_draft call'), plus the refusal condition for accounts without timed publishing. However it never disambiguates edit_schedule from siblings like update_draft or generate_draft, which also touch drafts.

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