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

Annotations already declare readOnlyHint=false, destructiveHint=false, and openWorldHint=true, so the safety and external-side-effect profile is covered by structured data. The description adds the meaningful scheduled-versus-immediate distinction, but omits behavior an agent would want for a multi-target write: partial failure semantics, retry/idempotency expectations, and whether one bad target rejects the whole request.

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 with no filler; the core action is front-loaded and the scheduling modifier follows. Nothing is repeated from the annotations title in a wasteful way.

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?

An output schema exists, so return values need not be described, and the input schema is densely annotated for platform options. Still, for a 7-parameter write tool with scheduling, idempotency, and partner-account scoping, the description leaves out idempotency behavior and the create_post versus create_draft versus publish_post decision, which is the main thing an agent needs to choose 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?

Top-level schema description coverage is only 14%, so the description must carry weight; it explains `publish_at` semantics, which the schema leaves as an undescribed string, and clarifies the multi-target nature of `targets`. It says nothing about `idempotency_key`, `external_id`, `external_user_id`, or `media`, though the nested schema properties do carry substantial inline documentation.

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 ("Creates one logical post") plus a distinguishing scope note that a single post fans out to multiple connected accounts. It does not, however, distinguish this tool from close siblings such as create_draft or publish_post, so an agent must infer the boundary.

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?

Provides one useful routing rule: including `publish_at` schedules rather than sends immediately. It says nothing about when to prefer create_post over create_draft or publish_post, nor about prerequisites such as targets having to reference connected accounts.

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