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

Annotations clearly declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the description need not repeat these. The description adds a valuable behavioral trait: bulk support via speech_engine_ids. However, it doesn't disclose response format, error behavior, or what happens when both id and ids are provided. Given the annotations cover safety, a score of 3 is appropriate.

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 short and front-loaded with the purpose, but the second sentence about bulk support is useful and earns its place. It lacks structure (e.g., bullet points for parameters) but that's acceptable for a brief description. However, it is under-specified, which is not the same as conciseness.

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 no output schema and sparse annotations, the description must provide more context. It fails to mention return type (e.g., does it return a single engine or a list?), error conditions, or any configuration details. The bulk support hint is a plus, but for a tool with only 3 parameters, it's incomplete.

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%, meaning the description is the sole source of parameter meaning. It only mentions speech_engine_ids for bulk usage, but does not explain speech_engine_id or account. It fails to compensate for the lack of schema descriptions, leaving the agent to guess the role of each parameter.

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 'Get Speech Engine. Retrieve a Speech Engine resource' restates the name with minimal elaboration. It fails to distinguish this from sibling tools like elevenlabs_get_speech_history, elevenlabs_get_voice_by_id, or even elevenlabs_list_speech_engines—what makes a 'Speech Engine' unique? The bulk support hint is useful but the core purpose remains vague.

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 no context on when to use this tool versus alternatives, such as when to use list_speech_engines instead. It does not mention required parameters, nor the relationship between speech_engine_id and speech_engine_ids (e.g., are they mutually exclusive?). No exclusions or prerequisites are stated.

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