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

With no annotations provided, the description carries the full burden of behavioral disclosure, and it delivers: it reveals the async nature, the immediate return of id plus credits_charged, the cost model (0.1 credits per character rounded up), the terminal status values (complete, error, canceled), and the contents of completed projects (downloads with direct URLs). This is exactly the kind of non-obvious runtime behavior an agent needs.

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 well-structured: a one-sentence purpose statement, a one-sentence cost note, then a dense but purposeful MCP guidance bullet. Everything earns its place and the most important facts are front-loaded; the only minor issue is that the guidance bullet packs several pieces of workflow information into one long run-on section.

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?

The trickiest aspects of this tool — asynchronous execution, immediate vs. final results, how to retrieve output, and cost accounting — are all fully covered. An output schema exists so return values are structured, and the description correctly routes the agent to wait_for_audio_project. It could mention failure causes or the 1000-character limit, but those are either in the schema or minor 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 baseline is 3. The description adds the cost-per-character detail that contextualizes the prompt parameter, but it does not explain how to construct the nested style object or add meaning beyond what the schema already documents, so it stays at baseline.

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 first sentence, 'Generate speech from text,' states a specific verb and resource clearly. However, it does not explicitly distinguish itself from the close sibling ai_voice_cloner_create_audio, which also creates audio, so it misses the differentiation needed for a 5.

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 MCP guidance section gives clear post-invocation workflow context: call wait_for_audio_project with the returned id or poll until status is terminal, and it describes what completed projects contain. However, it never explicitly states when to use this tool versus alternatives like ai_voice_cloner_create_audio, leaving selection to implication from the tool's name and purpose.

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