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

Annotations already declare destructive/non-idempotent/open-world behavior, but the description adds genuine behavioral context beyond them: it refuses when status!=approved, and it imposes a YouTube-specific obligation to display a certification line before calling. That compliance/precondition detail is not derivable from structured fields.

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?

Three tight sentences, front-loaded with the core action, then preconditions, then the special-case YouTube requirement. Every sentence carries load; nothing is redundant.

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 write action with full schema coverage, no output schema, and annotations covering the safety profile, nothing an agent needs to invoke it correctly is missing. The approval precondition and YouTube certification requirement close the important gaps.

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 100%, so the schema already documents all four parameters, including that postId must be approved and where connectionId comes from. The description reinforces ordering but adds little syntax or meaning beyond the schema, so baseline 3 applies.

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 ('Publishes an already-approved post') and explicitly distinguishes itself from the sibling schedule_post by calling itself 'the on-demand equivalent of schedule_post.' The scope ('already-approved,' 'immediately') is unambiguous.

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?

Gives explicit prerequisites and routing: call approve_post first, call list_connections first for connectionId, and use schedule_post instead when scheduling. Both the when-to-use and the alternative are named.

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