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

Annotations already indicate this is a mutating operation (readOnlyHint=false). The description adds useful context about creation modes (blank or from URL) and bulk execution, but does not disclose side effects, authentication needs, or behavior when from_url is null. This is adequate but not rich.

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?

The description is concise and front-loaded with the core purpose. The 'Bulk support' line adds useful information without waste. Minor redundancy exists in 'Create Chapter' followed by 'Creates a new chapter,' but overall it is efficient.

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?

With 5 parameters, 0% schema coverage, no output schema, and sparse annotations, the description leaves notable gaps: it does not explain account, the relationship between project_id and project_ids, or expected return behavior. It covers the primary use case but is incomplete for a tool with this 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%, so the description must compensate. It explains from_url and project_ids, but leaves name, project_id, and especially account undefined. The parameter names are partially self-explanatory, but account is ambiguous and no additional meaning is provided.

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 clearly states the tool's function: 'Creates a new chapter either as blank or from a URL.' This is a specific verb+resource pairing that distinguishes it from sibling tools like elevenlabs_edit_chapter and elevenlabs_delete_chapter_endpoint by emphasizing 'new' chapter creation.

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 description provides clear context for when to use the tool: when creating a chapter, with the option to create blank or from a URL. It also mentions bulk support via project_ids. However, it does not explicitly state when not to use it or name alternatives like edit_chapter.

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