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

Annotations declare a non-destructive mutation, and the description adds useful context beyond them: no credit cost and the consequence of going public ('anyone can use its finished looks and clips'). It doesn't state whether previously published material stays public on revert, but coverage is good.

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 primary action and followed by constraint and cost. No 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?

Output schema exists so return values need no explanation, and annotations cover the safety profile. The description covers ownership, effect, and cost; only edge behavior (e.g., renaming while public) is left unstated.

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% (baseline 3), and the description still adds meaning: the 'public' flag's effect is spelled out as sharing finished looks and clips, and reverting to private is described. Name and character semantics align with the schema.

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 specific verbs (rename, make public/private) and the exact resource (one of the user's own AI influencers). Distinguishes itself clearly from create_character, delete_character, get_character and list_characters in the sibling set.

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?

Explicit scope constraint: 'Only the user's own; the public cast belongs to ClipUGC,' which tells the agent when this tool will not apply. It doesn't name a sibling alternative for non-owned characters, but the when-not condition is clear.

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