tool_synthesize_speech

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

With no annotations available, the description carries the behavioral transparency burden, and it does so well: it discloses the ASMR pipeline order, default passthrough behavior, when output becomes stereo, and the exact return dict fields. It slightly overstates by saying 'All ASMR params default to OFF' when highpass_cutoff_hz defaults to 60 Hz (always on), which is a minor accuracy gap.

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 with clear sections: purpose, three usage modes, return value, and pipeline. It is dense but every sentence contributes useful information, and the most important decision (which mode to use) is front-loaded.

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 16-parameter tool with no output schema, the description is unusually complete: it explains usage modes, return contents, effect pipeline, and stereo behavior. The main gap is that it never explicitly states that voice_name, instruct, or both are effectively required, despite the schema only listing text as required. This could lead an agent to attempt a call with only text.

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 genuine semantic value beyond the schema by explaining how voice_name and instruct interact in the hybrid mode, how the ASMR pipeline orders effects, and when stereo output is triggered. This goes beyond the individual parameter descriptions.

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 opens with a specific, action-oriented statement: 'Generate speech audio with a cloned voice OR voice design, or both.' It clearly identifies the resource (speech audio) and the two primary input sources, and the three usage modes make it easy to distinguish this synthesis tool from sibling tools like clone_voice_from_audio or design_voice.

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 three usage modes provide explicit, actionable instructions: pass voice_name only, pass instruct only, or pass both. It also references voice_name coming from a prior clone_voice_from_audio call, which helps route the workflow. However, it does not explicitly name sibling alternatives or say when not to use this tool, so it stops short of full when-vs-alternatives guidance.

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