elevenlabs_voice_lines

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

No annotations are provided, so the description carries the full burden. It implies a write operation that creates timeline clips, but says nothing about which track they land on (the audioTrack param default A2 is only in the schema), whether existing content is overwritten, what happens on partial failure, or that an ElevenLabs API key/voice must be configured.

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?

One sentence, front-loaded with the core action and behavior, with the example parenthetical earning its place as the only usage cue. Nothing redundant.

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 mutation tool that generates multiple audio assets and places them on a timeline, with no annotations, no output schema, and half the parameters undocumented, the description leaves the agent guessing about track targeting, overwrite behavior, and how to pick a voice. It is significantly under-specified for 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 coverage is only 38% across 8 parameters, and the description addresses just the line objects ('one clip per line', 'at its time'). The six voice-tuning parameters (speed, style, stability, similarityBoost, modelId, voiceId) and audioTrack are never explained in the description, and three of them have no schema description either.

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?

Names a specific verb and resource: generate one voiceover clip per line and place each at its time. That distinguishes it operationally from elevenlabs_generate_speech, though it never names that sibling explicitly, so the differentiation is inferred rather than stated.

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 parenthetical 'e.g. narration matching captions' gives one concrete usage scenario, which is genuine context. However, there is no explicit when-to-use versus when-not guidance and no pointer to elevenlabs_generate_speech for a single clip or to add_captions for the caption side of the workflow.

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