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

Annotations already declare a non-read-only, non-destructive, closed-world mutation, so the safety profile is covered. The description adds genuine behavioral context — starting the plan causes briefs to be written on their scheduled dates — but omits whether the action is reversible (e.g., via a pause), what happens if the plan is not yet reviewed, and idempotency.

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?

A single front-loaded sentence that states the action and its consequence with no filler. Nothing in it could be trimmed without losing meaning.

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 three-parameter mutation with a real downstream effect (briefs get written), the description leaves the parameter sourcing and the returns unaddressed, and no output schema exists to offload that burden. Annotations cover safety only, so the definition is thin for the operation's complexity.

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% and all three identifiers (projectId, siteId, planId) are required and undocumented in both schema and description. The description says nothing about how these are obtained or which is the authoritative scope, so it fails to compensate for the coverage gap.

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?

Specific verb ('Start') plus resource ('a reviewed content plan') and an outcome ('its briefs are written on their scheduled dates'), which is clear enough to act on. It does not, however, name or explicitly distinguish itself from close siblings like generate_content_plan, decide_content_plan, or update_content_automation.

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 word 'reviewed' implies a prerequisite state (the plan must have been decided/approved first) and 'scheduled dates' implies the plan is already scheduled, so usage context is inferable. But there is no explicit when-to-use/when-not-to-use guidance and no mention of the alternative that produces the plan in the first place.

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